SOLUTION: Use the formula x = -b+_ square root b^2-4ac over 2a to solve the equation 3x^2 = 2x +5

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Question 807337: Use the formula x = -b+_ square root b^2-4ac over 2a to solve the equation 3x^2 = 2x +5
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 3x%5E2%2B-2x%2B-5+=+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=%28-2%29%5E2-4%2A3%2A-5=64.

Discriminant d=64 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--2%2B-sqrt%28+64+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-2%29%2Bsqrt%28+64+%29%29%2F2%5C3+=+1.66666666666667
x%5B2%5D+=+%28-%28-2%29-sqrt%28+64+%29%29%2F2%5C3+=+-1

Quadratic expression 3x%5E2%2B-2x%2B-5 can be factored:
3x%5E2%2B-2x%2B-5+=+3%28x-1.66666666666667%29%2A%28x--1%29
Again, the answer is: 1.66666666666667, -1. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+3%2Ax%5E2%2B-2%2Ax%2B-5+%29