SOLUTION: Solve for c in (c - 7)^2 = 81 + 20c.

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Question 1209147: Solve for c in (c - 7)^2 = 81 + 20c.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
c%5E2-14c%2B49=20c%2B81
c%5E2-34c-32=0
discriminant, %28-34%29%5E2-4%2A1%2A%28-32%29=1156%2B128=1284
6%2A214=2%2A6%2A107=2%2A2%2A3%2A107, solving for c by factorization not useful
because discriminant not a perfect square.

c=%2834%2B-+sqrt%282%2A2%2A3%2A107%29%29%2F2
highlight%28c=17%2B-+sqrt%28321%29%29