SOLUTION: Divide 16 into two parts such that the square of the bigger number is 64 more than the square of the smaller number.

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Question 992486: Divide 16 into two parts such that the square of the bigger number is 64 more than the square of the smaller number.
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
We divide 16 into two parts/numbers: x and y , so that
x%2By=16 , and we say that
x= the bigger number, and
y= the smaller number.
It is not explicitly stated, but I suspect that the wording implies that x and y are both positive numbers, and probably positive integers.
The phrase "the square of the bigger number is 64 more than the square of the smaller number" translates as
x%5E2=y%5E2%2B64<--->x%5E2-y%5E2=64 .
Now we have a system of two equations:
system%28x%5E2-y%5E2=64%2Cx%2By=16%29 or system%28x%5E2=y%5E2%2B64%2Cx%2By=16%29 .
From there, we can take different roads to the solution.

ONE WAY:
system%28x%5E2-y%5E2=64%2Cx%2By=16%29--->system%28%28x%2By%29%28x-y%29=64%2Cx%2By=16%29--->system%28%28x%2By%29%28x-y%29%2F%28x%2By%29=64%2F16%2Cx%2By=16%29--->system%28x-y=4%2Cx%2By=16%29--->system%28x-y%2Bx%2By=4%2B16%2Cx%2By=16%29--->system%282x=20%2Cx%2By=16%29--->system%28x=10%2Cx%2By=16%29--->system%28x=10%2C10%2By=16%29--->system%28x=10%2Cy=16-10%29--->highlight%28system%28x=10%2Cy=6%29%29

ANOTHER WAY:
system%28x%5E2=y%5E2%2B64%2Cx%2By=16%29--->system%28x%5E2=%2816-x%29%5E2%2B64%2Cy=16-x%29--->system%28x%5E2=256-32x%2Bx%5E2%2B64%2Cy=16-x%29--->system%280=320-32x%2Cx%2By=16%29--->system%2832x=320%2Cx%2By=16%29--->system%28x=320%2F32%2Cx%2By=16%29--->system%28x=10%2Cx%2By=16%29--->system%28x=10%2C10%2By=16%29--->system%28x=10%2Cy=16-10%29--->highlight%28system%28x=10%2Cy=6%29%29

A "CHEATING" WAY:
x%5E2=y%5E2%2B64<--->x%5E2=y%5E2%2B8%5E2
A right triangle with legs measuring y and 8 has a hypotenuse measuring x .
Look up a table of Pythagorean triples.
In that table you would find, in the first two columns,
8 and y (not necessarily in that order.
The third column will show x .
In the first few rows you find two choices:
matrix%282%2C3%2C6%2C8%2C10%2C8%2C15%2C17%29
The first choice gives
y=6%2Cx=10%2Cx%2B10=6%2B10=16%29 and shows you the solution.
The other row shows
y=15%2Cx=17%2Cx%2By=15%2B17=32%29 and has nothing to do with the solution.