SOLUTION: Solve for u. U^2 - U - 12 = 0

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Question 667359: Solve for u.
U^2 - U - 12 = 0
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

U%5E2+-+U+-+12+=+0....use quadratic formula
as you can see, a=1, b=-1, and c=-12

U+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

U+=+%28-%28-1%29+%2B-+sqrt%28%28-1%29%5E2-4%2A1%2A%28-12%29+%29%29%2F%282%2A1%29+

U+=+%281+%2B-+sqrt%281%2B48+%29%29%2F2+

U+=+%281+%2B-+sqrt%2849+%29%29%2F2+

U+=+%281+%2B-+7%29%2F2+

solutions:

U+=+%281+%2B+7%29%2F2+

U+=+8%2F2+

highlight%28U+=+4%29+

and

U+=+%281+-+7%29%2F2+

U+=+-6%2F2+

highlight%28U+=+-3%29+