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Factor x^2-5x-24 i need help to figure this out

User Mark Vanzuela
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1 Answer

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22 votes

Answer:

(x-8)(x+3)

Explanation:

1) Find out what are the factors of the constant?

2) Which of those add to equal the coefficient before the x value?

In this particular equation, we have the constant being 24. The first two factors that come to mind are 6 and 4, and 8 and 3. Since it is -24, we need one of these numbers to be negative.

Let's look at our "b" value, or the coefficient behind the x value, 5. Looking at our factors and thinking of addition (since one of them must be negative, it will most likely be subtraction instead of addition) I can see that

8+ −3=5

which is one of the factors of -24.

This means that we can factor our equation using these numbers, getting us the following:

(x−3)(x+8)

Hope this helped!

User Diastrophism
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