First put the equation under one denominator.
17/1+2/√22 = (17√22 + 2)/√22
rationalize this equation by multiplying both numerator and denominator by √22.
= (17×√22×√22 + 2×√22)/(√22×√22)
= (17×22 +2√22)/22
= (374 +2√22)/22
So, from the equation,
√ (17+2√22) = √((374 + 2√22)/22)