8th Grade Relations and Functions Unit Review

Which Equation Describes the function shown by the table?

• A) y = $\frac{-5}{2}x$

• B) y = $\frac{5}{2}x$

• C) y = $\frac{2}{5}x$

• D) y = $\frac{-2}{5}x$

Is the relation a function?

• A) Yes, each input has exactly one output

• B) Yes, each output has exactly one input

• C) No, each output has more than one input

• D) No, each input only shares an output

Evaluate the function when x = -2, 3, & 9.

g(x)=-2x+1

• A) g(-2)=-5, g(3)=7, g(9)=20

• B) g(-2)=5, g(3)=7, g(9)=20

• C) g(-2)=5, g(3)=-5, g(9)=-17

• D) g(-2)=11, g(3)=-5, g(9)=-17

Use the graph to write a linear function that relates y to x.

• A) $y=\frac{3}{2}x-2$

• B) $y=\frac{2}{3}x\ -\ 2$

• C) $y=-3x\ +\ 2$

• D) $y\ =\ 3x\ -\ 2$

Which graph matches the function y=-x+4

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Does the table represent a linear or nonlinear function?

• A) linear

• B) nonlinear

Which equation represents the nth term of the arithmetic sequence? -3, -1, 1, 3, ...

• A) $a_{n\ }=\ -n\ +\ 1$

• B) $a_{n\ }=\ 3n\ -\ 1$

• C) $a_n=\frac{1}{2}n\ -\ 2$

• D) $a_n=2n-3$

The table shows the number y lollipops made in x batches. What is the missing y-value that makes the table represent a linear function?

• A) 44

• B) 42

• C) 64

• D) 48

Use the table to write a linear function that relates y to x.

• A) y = x - 4

• B) y = -x + 4

• C) y = x + 4

• D) y = -x - 4

The graph shows the heating bill cost at your house. Describe the change in usage from January to May.

• A) The heating cost increases as the months increase.

• B) The heating cost increases as the months decrease.

• C) The heating cost decreases as the months decrease.

• D) The heating cost decreases as the months increase.