Evaluate and Compare Functions

Which function could have produced the values in the table?

• y = –x ─ 14

• y = -3x + 2

• y = 3x ─ 22

• y = 3x + 2

Answer explanation

The equation that works for all pairs in the table is

y = 3x + 2

-10 = 3(-4) + 2 | -10 = -12 + 2

-7 = 3(-3) + 2 | -7 = -9 + 2

-4 = 3(-2) + 2 | -4 = -6 + 2

-1 = 3(-1) + 2 | -1 = -3 + 1

2 = 3(0) + 2 | 2 = 0 + 2

Make sure you test each of the values of the table. When you come across a false statement, you know that can't be the equation.

Tags

CCSS.8.F.B.4

CCSS.HSF.LE.A.2

Which relations defines y as a function of x?

• y = 2.4x

• 
• 

Answer explanation

The equation y = 2.4x has one y value for every x value.

The table has 2 y values for x = 4 meaning it is not a function.

The inequality graph has multiple y values for every x value.

Functions do not have exponents (other than 1) on the y variable.

Tags

CCSS.8.F.A.1

Which equation defines p as a function of t?

• p = 3t + 2

• t = 3p + 2

• p = 0t + 2

• t = 0p + 2

Answer explanation

To describe p as a function of t, p must be the dependent variable.

p = 3t + 2 | as t changes, p will change

t = 3p + 2 | as p changes, t will change

p = 0t + 2 | this one is p = 2, it does not matter what t is

t = 0p + 2 | this on is t = 2, it does not matter what t is

p = 3t + 2 is the answer

Tags

CCSS.8.F.B.4

CCSS.HSF.LE.A.2

Select all ordered pairs that correspond to (input, output) pairs for the function

y = —6x + 7

• (1, 1)

• (–1, 1)

• (–6, 7)

• (3, –11)

Answer explanation

Solutions for y = —6x + 7

(1, 1) | 1 ? -6(1) + 7 ? 1 = -6 + 7 | 1 = 1 | Yes

(–1, 1) | 1 ? (-6)(-1) + 7 ? 6 + 7 |

1 = 13 | No

(–6, 7) | 7 ? (-6)(-6) + 7 ? 36 + 7 | 7 = 43 | No

(3, –11) | -11 ? (-6)(3) + 7 ? -18 + 7 | -11 = -11 | Yes

Tags

CCSS.8.F.A.1

CCSS.HSF.IF.A.1

Compare the functions

g(0)=​ (a)   and h(0)=​ (b)  

so

g(0) ​ (c)   h(0)​

• 7

• 6

• >

• <

Tags

CCSS.8.F.A.2

CCSS.HSF.IF.C.9

Evaluate the function at h(-5).

Mathematical Equivalence

ON

Tags

CCSS.HSF.IF.A.2

Match the following function notation values

• 8

• f(0)

• -3

• f(-2)

• -7

• f (x) = -1

• -6

• f(6)

• -4

• f (x) = -8

Tags

CCSS.HSF.IF.A.2

complete the table using the function

f(x) = 2 ( x + 2 ) + 4x

c

d

e

f

2

64

20

15

4

32

Tags

CCSS.HSF.IF.A.2

f(-2)=​ (a)  

g(-2)=​ (b)  

h(-2)=​ (c)  

• 3

• 6

• -3

• -6

• 5

• -5

• 11

• -11

Tags

CCSS.HSF.IF.A.2

Evaluate the function. When ​ (a)   is 2, ​ (b)   is 3.

• x

• y

Tags

AI.9.12.A