Question

Evaluate 3x^2- 9 when x=-2

Answer 1

3

Explanation:

3x^2- 9 =

= 3(-2)² - 9

= 3×4 - 9

= 12 - 9

= 3

Answer 2

3

Explanation:

We know x = -2, so we can substitute -2 in for x

3x^2- 9

3*-2^2-9

Solve the exponent first (PEMDAS)

3*4-9

Multiply next

12-9

Subtract

3