SOLUTION: 3^2+x + 3^2-x = 82

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Question 838674: 3^2+x + 3^2-x = 82
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Let u=3%5Ex, 3%5E%282%2Bx%29=9%2A3%5Ex=9u, 3%5E%282-x%29=9%2F3%5Ex=9%2Fu
3%5E%282%2Bx%29+%2B+3%5E%282-x%29+=+82
9u%2B9%2Fu=82
9u%5E2%2B9=82u
9u%5E2-82u%2B9=0
%289u-1%29%28u-9%29=0
Two solutions:
9u-1=0
9u=1
u=1%2F9
3%5Ex=1%2F9
x=-2
and
u-9=0
u=9
3%5Ex=9
x=2