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kirza4 [7]
3 years ago
9

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

Mathematics
2 answers:
murzikaleks [220]3 years ago
6 0

Answer:

3

Step-by-step 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

FrozenT [24]3 years ago
3 0

Answer:

3

Step-by-step explanation:

3x^2- 9 =

= 3(-2)² - 9

= 3×4 - 9

= 12 - 9

= 3

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