Question

8.

Evaluate the function rule for the given value. y = 12 • 3^x for x = –2

A. 4/9
B. 4/3
C. –72
D. 4

Answer 1

B

Explanation:

y= 12 *3 ^x , substitute x with -2

y=12 *3^-2 , use the rule a^ - b = 1 /a^b

y= 12 / 3^2 , 3^2 =3*3 = 9

y= 12/9, divide both numbers by 3, 12÷3/ 9÷3

y= 4/3

Answer 2

B

Explanation:

Using the rule of exponents

`a^(-m)` =
`(1)/(a^(m) )`

Given

y = 12 ×
`3^(x)` ← substitute x = - 2 into the expression

y = 12 ×
`3^(-2)` = 12 ×
`(1)/(3^(2) )` = 12 ×
`(1)/(9)` =
`(12)/(9)` =
`(4)/(3)` → B