Factor the Trinomial.

4u^2+4u-15

Question

Factor the Trinomial.

4u^2+4u-15

noelgreco · Answer

Multiply a by c.  What do you get?

anonymous · Answer

So multiply 4u^2 by -15 ?

noelgreco · Answer

No, the standard form of a quadratic is ax^2+bx+c

anonymous · Answer

If that is the case you would multiply 4 by -15 therefore it gives us -60, then ?

noelgreco · Answer

Don't worry about the negative.

Find two factors of 60 whose difference is 4 (the value of b in this quadratic)

anonymous · Answer

6 and 10?

noelgreco · Answer

Good. Now we're going to rewrite the original quadratic as

4u^2 + 10u - 6u - 15

Note that the original b term has been split up into the two numbers you gave me as factors of 60 (10-6=4)

Now factor out the GCF in the first two terms, and the GCF in the second pair of terms.

anonymous · Answer

Okay think I got it, so it leaves us with 2u(u+5)(3u-5)?

noelgreco · Answer

It should look like this:

2u(2u+5)-3(2u+5) =(2u+5)(2u-3)

This method probably looks complicated, but if you study it and use it when a is not = 1 you'll save a bunch of guess and check.

Good luck.

anonymous · Answer

Thank you again, Almost done, have a few more math problems to try to solve that I just can't wrap my head around.