SOLUTION: 2x(SQUARED)=X+30

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Question 122432: 2x(SQUARED)=X+30
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
2x^2=x+30
2x^2-x-30=0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 2x%5E2%2B-1x%2B-30+=+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=%28-1%29%5E2-4%2A2%2A-30=241.

Discriminant d=241 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--1%2B-sqrt%28+241+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-1%29%2Bsqrt%28+241+%29%29%2F2%5C2+=+4.13104367406501
x%5B2%5D+=+%28-%28-1%29-sqrt%28+241+%29%29%2F2%5C2+=+-3.63104367406501

Quadratic expression 2x%5E2%2B-1x%2B-30 can be factored:
2x%5E2%2B-1x%2B-30+=+%28x-4.13104367406501%29%2A%28x--3.63104367406501%29
Again, the answer is: 4.13104367406501, -3.63104367406501. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-1%2Ax%2B-30+%29