SOLUTION: how do you solve 8x^-6x-5=0

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Question 189212: how do you solve 8x^-6x-5=0
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
how do you solve 8x^-6x-5=0
If you mean:
8x%5E2-6x-5=0 , then
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 8x%5E2%2B-6x%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=%28-6%29%5E2-4%2A8%2A-5=196.

Discriminant d=196 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--6%2B-sqrt%28+196+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-6%29%2Bsqrt%28+196+%29%29%2F2%5C8+=+1.25
x%5B2%5D+=+%28-%28-6%29-sqrt%28+196+%29%29%2F2%5C8+=+-0.5

Quadratic expression 8x%5E2%2B-6x%2B-5 can be factored:
8x%5E2%2B-6x%2B-5+=+%28x-1.25%29%2A%28x--0.5%29
Again, the answer is: 1.25, -0.5. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+8%2Ax%5E2%2B-6%2Ax%2B-5+%29

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The quadratic equation is best. You can waste your life trying to factor polynomials.