SOLUTION: 4 over x^2= 7 over x +2

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Question 617733: 4 over x^2= 7 over x +2
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
4%2Fx%5E2+=+7%2F%28x%2B2%29

4%28x%2B2%29+=+7x%5E2

4x%2B8+=+7x%5E2

0+=+7x%5E2-4x-8

7x%5E2-4x-8+=+0

7x%5E2-4x-8+=+0

Now use the quadratic formula to solve.

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

x+=+%28-%28-4%29%2B-sqrt%28%28-4%29%5E2-4%287%29%28-8%29%29%29%2F%282%287%29%29

x+=+%284%2B-sqrt%2816-%28-224%29%29%29%2F%2814%29

x+=+%284%2B-sqrt%28240%29%29%2F14

x+=+%284%2Bsqrt%28240%29%29%2F14 or x+=+%284-sqrt%28240%29%29%2F14

x+=+%284%2B4%2Asqrt%2815%29%29%2F14 or x+=+%284-4%2Asqrt%2815%29%29%2F14

x+=+%282%2B2%2Asqrt%2815%29%29%2F7 or x+=+%282-2%2Asqrt%2815%29%29%2F7

So the solutions are x+=+%282%2B2%2Asqrt%2815%29%29%2F7 or x+=+%282-2%2Asqrt%2815%29%29%2F7