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How do you Factor this polynomial equation? by grouping

X^2 + 9x - 2x - 18

User Zahara
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1 Answer

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Answer:

(x+9) (x-2)

Explanation:

The factors to this equation is (x+9) and (x-2).

You can get this by (1) grouping the the numbers, in this case the 9x and 2x will subtract and end up as 7x.

Your equation will now like this: x^2+7x-18

We can look at our equation using this formula now, ax^2+bx+c.

"a" is this case is 1, "b" is seen as 7, and "c" is -18.

From here we can find the factors that multiply to our "c" which is -18, but also add up to our "b" which is 7.

We can use our multiplication knowledge, and get the two factors of 9 and -2, and with these two numbers we then end up with the factors of (x+9) and (x-2).

User Guillermo Carone
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