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Factor completely 2x^2+21x-11
Can I get step by step instructions for this please?

User Li Yupeng
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1 Answer

2 votes

Answer: (x+11)(2x-1)

Explanation:

First, you want to look at the quadratic. Clearly it doesn't have any GCF. So what you have to do is multiply 2 to the c value: -11. To get:
x^(2) +21x-22

Second, you find the factors of -22 that add to 21.

I've isolated the factors to be 22 and -1. So like a regular quadratic you solve and "plug" it in. (x+22)(x-1)

Third, you can't forget about the multiplied 2. You have to distribute it by plugging the 2 back in front of x in both parenthesis groups. (2x+22)(2x-1)

As you can see, 2x+22 can be simplified. so you simplify, and you get(x+11)(2x-1).

User Janfy
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