SOLUTION: 2x - 5squareroot x + 2 =0

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Question 181029: 2x - 5squareroot x + 2 =0
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
2x-5sqrt(x+2)=0
2x=5sqrt(x+2)
4x^2=25(x+2) square each side.
4x^2=25x+50
4x^2-25x-50=0
x=[5(sqrt(57)+5)]/8 is the only correct answer for this problem.
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Ed
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 4x%5E2%2B-25x%2B-50+=+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=%28-25%29%5E2-4%2A4%2A-50=1425.

Discriminant d=1425 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--25%2B-sqrt%28+1425+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-25%29%2Bsqrt%28+1425+%29%29%2F2%5C4+=+7.84364652204422
x%5B2%5D+=+%28-%28-25%29-sqrt%28+1425+%29%29%2F2%5C4+=+-1.59364652204422

Quadratic expression 4x%5E2%2B-25x%2B-50 can be factored:
4x%5E2%2B-25x%2B-50+=+%28x-7.84364652204422%29%2A%28x--1.59364652204422%29
Again, the answer is: 7.84364652204422, -1.59364652204422. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+4%2Ax%5E2%2B-25%2Ax%2B-50+%29