SOLUTION: Solve for x x^2+72=12x

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Question 153089: Solve for x
x^2+72=12x
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x:
x%5E2%2B72+=+12x First, subtract 12x from both sides.
x%5E2-12x%2B72+=+0 The trinomial is not factorable, so use the quadratic formula: x+=+%28-b%2B-sqrt%28b%5E-4ac%29%29%2F2a, where a = 1, b = -12, and c = 72.
x+=+%28-%28-12%29%2B-sqrt%28%28-12%29%5E2-4%281%29%2872%29%29%29%2F2%281%29
x+=+%2812%2B-sqrt%28144-288%29%29%2F2
x+=+%2812%2B-sqrt%28-144%29%29%2F2
x+=+%2812%2B-12sqrt%28-1%29%29%2F2
x+=+6%2B6i or x+=+6-6i