f(x) = 4x - 11
g(x) = 2x² + 7x - 10
They ask you for (f o g)(x), so basically you need to replace the function g(x) in every x of the function f(x):
(f o g)(x) = f(g(x)) = 4( 2x² + 7x - 10 ) - 11
Using distributive property:
(f o g)(x) = f(g(x)) = 8x² + 28x - 40 - 11 = 8x² + 28x - 51