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2 votes
If Q(x) = 4x^2 + 5x -7, find Q(-1)

2 Answers

5 votes

Answer: -8

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Work Shown:

Q(x) = 4x^2 + 5x - 7

Q(-1) = 4(-1)^2 + 5(-1) - 7 .... replace every x with -1; use PEMDAS

Q(-1) = 4(1) + 5(-1) - 7

Q(-1) = 4 - 5 - 7

Q(-1) = -1 - 7

Q(-1) = -8

User Xiaoguo Ge
by
5.0k points
4 votes

Answer: -8

Explanation:

Q(x) = 4x² + 5x - 7

Q(-1) = 4(-1)² + 5(-1) - 7

= 4(1) + -5 -7

= 4 - 5 -7

= -8

User Sinky
by
4.6k points