SOLUTION: Solve x. x^2+2^x = 100

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Question 172677: Solve x.
x^2+2^x = 100
Found 2 solutions by Mathtut, Alan3354:
Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B2x-100=0
:
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B2x%2B-100+=+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=%282%29%5E2-4%2A1%2A-100=404.

Discriminant d=404 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-2%2B-sqrt%28+404+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%282%29%2Bsqrt%28+404+%29%29%2F2%5C1+=+9.04987562112089
x%5B2%5D+=+%28-%282%29-sqrt%28+404+%29%29%2F2%5C1+=+-11.0498756211209

Quadratic expression 1x%5E2%2B2x%2B-100 can be factored:
1x%5E2%2B2x%2B-100+=+%28x-9.04987562112089%29%2A%28x--11.0498756211209%29
Again, the answer is: 9.04987562112089, -11.0498756211209. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B2%2Ax%2B-100+%29

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Solve x.
x^2+2^x = 100
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mathtut used 2x instead of 2^x.
I was hoping to see someone solve this one, I don't know how.
I know that x = 6, but I don't know how to solve it.