SOLUTION: A number squared plus three times the number squared equals 81, find the number.

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Question 596766: A number squared plus three times the number squared equals 81, find the number.
Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
This could be written 2 different ways, so I'll solve both ways.
1) n^2+(3n)^2=81
10n^2=81
n^2=8.1
Sqrt both sides and we get:
n=2.846 (approx)
2)n^2+3n^2=81
4n^2=81
n^2=20.25
Sqrt
n=4.5
Make sense?
RJ
www.math-unlock.com