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No calculator

Translate the point $A(-4, -4)$ by 2 units right and 1 units down. Tap its image $A'$ .
No calculator

Dilate $A(3, 1)$ about the origin with scale factor 2. Tap its image.
No calculator

$y$ is proportional to $x$ . When $x = 2$ , $y = 10$ . Find the constant of proportionality $k$ in $y = kx$ .
No calculator

Solve $3x + 3 = -18$ . $x = \;?$
No calculator
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (5, 1), (5, 2), (9, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 5 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (4, 1), (4, 2), (6, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 4 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (2, 1), (2, 2), (8, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 2 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (3, 1), (3, 2), (7, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 3 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (4, 1), (4, 2), (9, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 4 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (5, 1), (5, 2), (6, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 5 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (4, 1), (4, 2), (7, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 4 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (2, 1), (2, 2), (9, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 2 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (1, 1), (1, 2), (9, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 1 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (5, 1), (5, 2), (8, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 5 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (5, 1), (5, 2), (7, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 5 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (1, 1), (1, 2), (8, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 1 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (3, 1), (3, 2), (6, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 3 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (3, 1), (3, 2), (8, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 3 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (1, 1), (1, 2), (6, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 1 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (2, 1), (2, 2), (6, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 2 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (1, 1), (1, 2), (7, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 1 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (2, 1), (2, 2), (7, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 2 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (3, 1), (3, 2), (9, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 3 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
A table pairs inputs $x$ with outputs $y$ : $(x, y) = (4, 1), (4, 2), (8, 3)$ . Is $y$ a function of $x$ ?
1. No: the input 4 has two different outputs
2. Yes: every input has an output
3. Yes: the outputs are all different
No calculator
A scatterplot of car age against resale value has $r = -0.94$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.92$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.90$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.89$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.86$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.91$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.95$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.93$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.87$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.88$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
A scatterplot of car age against resale value has $r = -0.85$ . How would you describe the relationship?
1. Strong, negative, linear: older cars tend to be worth less
2. Weak, because r is negative
3. Each extra year causes a fixed loss of value
No calculator

$6^{ 2 } \cdot 6^{ 5 } = 6^{?}$ . What is the exponent?
No calculator

A square has an area of 225 square units. How long is its side?
No calculator

Reflect $A(3, 2)$ across the $x$ -axis. Tap its image.
No calculator

Two polygons are similar. A side of length 5 corresponds to a side of length 15. Another side of the small polygon has length 9. Find the matching side of the large one.
Rotate $A(1, 3)$ by $90^\circ$ counterclockwise about the origin. Tap its image.
Two triangles each have a $76^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $43^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $35^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $69^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $65^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $67^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $73^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $51^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $30^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $32^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $60^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $33^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $39^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $61^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $47^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $70^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $31^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $79^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $46^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $58^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $44^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $57^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $40^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $53^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $45^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $41^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $62^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $34^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $38^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $78^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $66^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $37^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $55^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $48^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $59^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $63^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $71^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $56^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $54^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $52^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $68^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $75^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $72^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $50^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $49^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $74^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $77^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $42^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $80^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
Two triangles each have a $36^\circ$ angle and a $50^\circ$ angle. What can you conclude?
1. They are similar (AA)
2. They are congruent
3. Nothing without side lengths
A gym charges 55 dollars to join and 19 dollars per month. Write the total cost $y$ after $x$ months.
How many solutions has $3(x + 2) = 3x + 6$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $9(x + 2) = 9x + 18$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $6(x + 7) = 6x + 42$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $3(x + 3) = 3x + 9$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $8(x + 5) = 8x + 40$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $2(x + 1) = 2x + 2$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $3(x + 4) = 3x + 12$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $8(x + 7) = 8x + 56$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $4(x + 9) = 4x + 36$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $3(x + 9) = 3x + 27$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $9(x + 1) = 9x + 9$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $4(x + 2) = 4x + 8$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $2(x + 7) = 2x + 14$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $5(x + 4) = 5x + 20$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $7(x + 8) = 7x + 56$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $9(x + 8) = 9x + 72$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $6(x + 2) = 6x + 12$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $5(x + 9) = 5x + 45$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $2(x + 8) = 2x + 16$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $7(x + 2) = 7x + 14$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $9(x + 7) = 9x + 63$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $7(x + 3) = 7x + 21$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $7(x + 1) = 7x + 7$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $9(x + 5) = 9x + 45$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $8(x + 4) = 8x + 32$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $7(x + 6) = 7x + 42$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $3(x + 8) = 3x + 24$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $7(x + 9) = 7x + 63$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $2(x + 4) = 2x + 8$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $7(x + 5) = 7x + 35$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $5(x + 6) = 5x + 30$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $4(x + 8) = 4x + 32$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $6(x + 3) = 6x + 18$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $6(x + 6) = 6x + 36$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $8(x + 3) = 8x + 24$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $4(x + 5) = 4x + 20$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $5(x + 2) = 5x + 10$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $3(x + 6) = 3x + 18$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $3(x + 7) = 3x + 21$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $3(x + 5) = 3x + 15$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $6(x + 1) = 6x + 6$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $5(x + 7) = 5x + 35$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $8(x + 1) = 8x + 8$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $6(x + 4) = 6x + 24$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $7(x + 7) = 7x + 49$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $4(x + 7) = 4x + 28$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $2(x + 2) = 2x + 4$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $4(x + 6) = 4x + 24$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $7(x + 4) = 7x + 28$ ?
1. Infinitely many
2. Exactly one
3. No solution
How many solutions has $4(x + 4) = 4x + 16$ ?
1. Infinitely many
2. Exactly one
3. No solution
$f(x) = 2x^2 + 3$ . Find $f(-3)$ .
$r = 0.6$ , $s_x = 15$ and $s_y = 16$ . Find the slope of the least-squares regression line of $y$ on $x$ .
Write $5^{-1}$ as a fraction.
Which number is irrational?
1. $\sqrt{ 2 }$
2. $\sqrt{ 4 }$
3. $0.\overline{ 1 }$
Which number is irrational?
1. $\sqrt{ 10 }$
2. $\sqrt{ 16 }$
3. $0.\overline{ 3 }$
Which number is irrational?
1. $\sqrt{ 37 }$
2. $\sqrt{ 49 }$
3. $0.\overline{ 6 }$
Which number is irrational?
1. $\sqrt{ 26 }$
2. $\sqrt{ 36 }$
3. $0.\overline{ 5 }$
Which number is irrational?
1. $\sqrt{ 5 }$
2. $\sqrt{ 9 }$
3. $0.\overline{ 2 }$
Which number is irrational?
1. $\sqrt{ 17 }$
2. $\sqrt{ 25 }$
3. $0.\overline{ 4 }$
Which number is irrational?
1. $\sqrt{ 65 }$
2. $\sqrt{ 81 }$
3. $0.\overline{ 8 }$
Which number is irrational?
1. $\sqrt{ 50 }$
2. $\sqrt{ 64 }$
3. $0.\overline{ 7 }$
Which number is irrational?
1. $\sqrt{ 82 }$
2. $\sqrt{ 100 }$
3. $0.\overline{ 9 }$
$\triangle ABC \cong \triangle DEF$ with $AB = 3$ , $BC = 11$ and $CA = 18$ . Find $DE$ .
Find the slope of the line through $(6, 2)$ and $(9, 8)$ .

Answers

$(-2, -5)$
$(6, 2)$
$5$
$-7$
No: the input 5 has two different outputs
Strong, negative, linear: older cars tend to be worth less
$7$
$15$
$(3, -2)$
$27$
$(-3, 1)$
They are similar (AA)
$19 x + 55$
Infinitely many
$21$
$\frac{16}{25}$
$\frac{1}{5}$
$\sqrt{ 2 }$
$3$
$2$