it has been over 5 years since i last took algebra and this stuff is dormant in my head. i know it's simple, but i can't remember it and the book is too advanced and doesn't explain it.
how do i factor the following:
6x²+7x-3=0
from what i can remember..... i know it has to go like this
(x__+___)(x__+___)
and that one side is the sum of 2 integers, and the other is the product of 2 integers... but i can't remember the order....
can you please help?
2007-09-08 17:06:00 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
6x²+3x-3=0
The first "x" has to be the product of 2 numbers that will equal the 6. The product of the last 2 numbers must equal -3. The sum of these must equal the middle 7x.
So, in this case, 6x² can be 6x or 3x or 2x or 1x
and the -3 can be -1, +1, -3 or +3
If you play with it a little, you will find that (2x -1)(3x +3) do the job. The product of the 2 middle ones plus the procuct of the two outer ones = -1(3x) + (2x)(+3) = 3x
2007-09-08 17:11:20 · answer #1 · answered by ignoramus 7 · 0⤊ 0⤋
Okay, I learned the following two years ago in Algebra I:
In your problem, 7 is the sum of the two numbers in the (x + _ )(x + _ ) and -3 is their product. (The secong monomial is the sum of the factors and the third monomial is their product.) You might went to list their factors out to help solve this. It's like using the FOIL method in reverse, sense you're starting with you're would-be FOIL answer. (FOIL being the way to solve (x + _ )(x + _ ) problems - First Outer Inner Last) Be careful when solving your problem because you have one postive number (7) and one negative (-3) so you need a postive factor and a negative one. It's basically trial and error. Oh!, and you'll have to factor out the 6. Um, like it should be (6x + _ )(x + _ ) or (x + _ )(6x + _ ). That should do it.
2007-09-08 17:23:24 · answer #2 · answered by Anonymous · 1⤊ 0⤋
FOIL: First, outside, inside, last.
(x+1)(x+2) would get you x^2 + 2x + 1x + 2, or x^2 + 3x + 2.
Are you sure that's the correct problem? I can get 6x^2 + 7x + 2 = 0 to work out...
2007-09-08 17:16:21 · answer #3 · answered by Corran 3 · 0⤊ 0⤋
6x^2+7x-3=0
(3x-1)(2x+3)=0
The 3x*2x=6x^2. Then you have 3*3x which equals 9x. Then you have -1*2x which equals -2x. Then you subtract -2x from 9x to get your middle term, 7x. Then -1*3 is -3, your third term. Hope this helps.
2007-09-08 17:39:42 · answer #4 · answered by Christi 4 · 1⤊ 0⤋