First use the Pythagorean Theorem which is a^2 + b^2 = c^2
Next you apply the numbers:
16^2 + 6^2 = c^2
Solve to find what number is equal to c^2:
256 + 36 = c^2
Last you apply the radicals to solve for c:
√292 = √c^2
√292 = √73 · 4 = √73 · 2 = 2√73
c = 2√73
