For how many real values of x is sqrt(120 - sqrt(x^2)) an integer?
Note that 120 - sqrt (x^2) must be a perfect square
Perfect squares
0 x = ± 120
1 x = ± 119
4 x = ± 116
9 x = ± 111
16 x = ± 104
25 x = ± 95
36 x = ± 84
49 x = ± 71
64 x = ± 56
81 x = ± 39
100 x = ± 20
22 values
