SOLUTION: x^2-x=56

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Question 620678: x^2-x=56
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-x=56

x%5E2-x-56=0

Now use the quadratic formula to solve for x

x+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29

x+=+%28-%28-1%29%2B-sqrt%28%28-1%29%5E2-4%281%29%28-56%29%29%29%2F%282%281%29%29

x+=+%281%2B-sqrt%281-%28-224%29%29%29%2F%282%29

x+=+%281%2B-sqrt%28225%29%29%2F2

x+=+%281%2Bsqrt%28225%29%29%2F2 or x+=+%281-sqrt%28225%29%29%2F2

x+=+%281%2B15%29%2F2 or x+=+%281-15%29%2F2

x+=+16%2F2 or x+=+-14%2F2

x+=+8 or x+=+-7

So the solutions are x+=+8 or x+=+-7