Question

√ x+10 +√ x-17=9

Answer 1

I assume you mean

√(x+10) + √(x-17) = 9
√(x+10) = 9-√(x-17)
x+10 = 81-18√(x-17)+x-17
18√(x-17) = 54
√(x-17) = 3
x-17 = 9
x = 26

check:
√(26+10)+√(26-17) = √36+√9 = 6+3 = 9
nope