SOLUTION: Hello. I am trying to factor this equation 15x^2 - 24x - 12. I then multiplied 15 x -12 = -180. From here I need to found -30 x 6 which if you subtract 6 from -30 = -24. so now th

Algebra.Com
Question 969380: Hello. I am trying to factor this equation 15x^2 - 24x - 12. I then multiplied 15 x -12 = -180. From here I need to found -30 x 6 which if you subtract 6 from -30 = -24. so now the equation looks like this:
15x^2 + 6x - 30x - 12. So I divide: 15x^2 + 6x/2x and -30x-12/-6 which now gave me 3x(5x+2)-6(5x+2) I continue to think my answer is (5x+2)(3x-6). unfortunately, the answer key has the answer as 3(5x+2)(x-2) what did I do wrong? Please help me.

Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39617)   (Show Source): You can put this solution on YOUR website!
Each term has a factor of 3:



There are only so few ways to factorize . Try a few combination of trinomial factorizations for the quadratic factor from the last step.

Look at the possible result for terms of x:

(5 2)(1 2)----------10 and 2, maybe.

(5 4)(1 1)---------5 and 4, NO.

(5 4 )(1 1)----------5 and 4, NO.

Look further at this: ;
You need and . Decide which signs within the binomials are needed.
......
This is what works: .

Your originally given expression also contained a factor of 3, so to finish your factorization of that, you have
.

Answer by MathTherapy(10552)   (Show Source): You can put this solution on YOUR website!
Hello. I am trying to factor this equation 15x^2 - 24x - 12. I then multiplied 15 x -12 = -180. From here I need to found -30 x 6 which if you subtract 6 from -30 = -24. so now the equation looks like this:
15x^2 + 6x - 30x - 12. So I divide: 15x^2 + 6x/2x and -30x-12/-6 which now gave me 3x(5x+2)-6(5x+2) I continue to think my answer is (5x+2)(3x-6). unfortunately, the answer key has the answer as 3(5x+2)(x-2) what did I do wrong? Please help me.
First, this is NOT an equation, but a TRINOMIAL that can be FACTORED.

The first step you need to take is to find the GCF
------ Factoring out GCF, 3
----- Factoring trinomial in the parentheses
Your answer is PARTIALLY correct. Since you didn't factor out a GCF, you can see that one of your
binomials, (3x - 6) can be factored as: 3(x - 2), thereby giving you: 3(x - 2)(5x + 2), which is
the same as mine and the answer in the answer key.
RELATED QUESTIONS

Could you please help me with this equation because the numbers seem out ragous and the... (answered by Nate)
Hello, I am trying to solve the following equation for x: 15x/4 = 9/4 + x-3/2... (answered by MathLover1,MathTherapy)
i need to factor this problem... (answered by Fombitz,scott8148)
Hi, I am trying to simplify the equation 15x2y x –x3/3y 15x to the power of 2 then (answered by sajal02)
I am trying to change this into slope-intercept form. The equation is 2x + 5y = 12. I... (answered by Alan3354,richwmiller)
I am trying to solve this problem using the quadratic formula but I need help. here is... (answered by Alan3354,fractalier,LinnW)
I am trying to figure this out but not sure if I have the correct answer:... (answered by Alan3354,edjones)
Hello. I am really stuck on my homework and need help. I am trying to solve this... (answered by ewatrrr)
Hello I need help for this equation x-2y=6 this is what I have:... (answered by checkley71)