How do you factor 4x^2+17x-15?

1 Answer
Mar 29, 2017

Use the slide and divide method to get (4x-3)(x+5).

Explanation:

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We'd use the slide and divide method.

Start by taking the a value, 4, and multiply it (also called sliding) with the c value, -15. Now we're working with the equation x^2+17x-60.

Then we'd factor it as normal, to get (x+20)(x-3). We have to bring the four back, and divide it from the 20 or the -3.

We'd get (x+(20)/4) and (x-(3)/4). We only have to divide from one binomial though, and the 20 is easiest to work with.

We'd then have 20/4=5, so we'd end up with (x+5).

We'd multiply the last 4, from the second binomial, over to x, and get 4x-3.

Combine the two to get (4x-3)(x+5).