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1 vote
Can Anyone help me with this and show your work please!

-2x² - 5x
X = -4

User Polarware
by
6.5k points

2 Answers

4 votes

Answer:

-2(-4)^2 - (5)(-4)

-2(-16) -( -20)

-32 +20

-12

Explanation:

User JoelAZ
by
6.9k points
7 votes

Answer:

-12

Explanation:

In this exercise, we have the following expression:


-2x^2-5x

So our goal is to plug in
x=-4 and find the output. To do so, let's rewrite the expression as a function of
x. So, we can write:


f(x)=-2x^2-5x

Then this is a quadratic function whose graph represents a parabola.

If
x=-4, we will find the output
f(-4), so:


f(-4)=-2(-4)^2-5(-4) \\ \\ f(-4)=-2(16)+20 \\ \\ f(-4)=-32+20 \\ \\ \boxed{f(-4)=-12}

So the correct answer is -12

User Zash
by
7.3k points