SOLUTION: please help me factor or complete the square {{{C}}} thanks

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Question 439100: please help me factor or complete the square
C
thanks
Found 2 solutions by jorel1380, unlockmath:
Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
6x2-7x=20
6x2-7x-20=0
(3x+4)(2x-5)=0
x=-4/3 or 5/2.
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 6x%5E2%2B-7x%2B-20+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-7%29%5E2-4%2A6%2A-20=529.

Discriminant d=529 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--7%2B-sqrt%28+529+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-7%29%2Bsqrt%28+529+%29%29%2F2%5C6+=+2.5
x%5B2%5D+=+%28-%28-7%29-sqrt%28+529+%29%29%2F2%5C6+=+-1.33333333333333

Quadratic expression 6x%5E2%2B-7x%2B-20 can be factored:
6x%5E2%2B-7x%2B-20+=+6%28x-2.5%29%2A%28x--1.33333333333333%29
Again, the answer is: 2.5, -1.33333333333333. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+6%2Ax%5E2%2B-7%2Ax%2B-20+%29

Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
First subtract 20 from both sides to get:
6x^2-7x-20=0
Factor:
(3x+4)(2x-5)
Now we can solve for x:
x=-4/3
x=5/2
There we go.
Make sense?
RJ
www.math-unlock.com