Question

The sum of the squares of two positive numbers is 9,so how much will the sum of their cubes be??

Answer 1

`27`

Explanation:

`x^2+y^2=9`

What squares can add up to 9?

`0 + 9 =sqrt 0 + sqrt3` Works!
`1 + 8` Neither are perfect squares
`2 +7` Neither are perfect squares
`3 +6` Neither are perfect squares
`4 +5` Neither are perfect squares
now repeats...

so only `0^2+3^2` works

`0^3+3^3 = 27`