SOLUTION: How do I solve for x in this equation? 6x^2 + 5x – 6 = 0

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Question 311356: How do I solve for x in this equation?
6x^2 + 5x – 6 = 0
Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
use quadratic equation ...u should memorize it
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 6x%5E2%2B5x%2B-6+=+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=%285%29%5E2-4%2A6%2A-6=169.

Discriminant d=169 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-5%2B-sqrt%28+169+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%285%29%2Bsqrt%28+169+%29%29%2F2%5C6+=+0.666666666666667
x%5B2%5D+=+%28-%285%29-sqrt%28+169+%29%29%2F2%5C6+=+-1.5

Quadratic expression 6x%5E2%2B5x%2B-6 can be factored:
6x%5E2%2B5x%2B-6+=+6%28x-0.666666666666667%29%2A%28x--1.5%29
Again, the answer is: 0.666666666666667, -1.5. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+6%2Ax%5E2%2B5%2Ax%2B-6+%29