We can compare the times the rockets each hit the ground by setting f(x)=0 and g(x)=0 and solving for each x.
-4x²+29x+24=0 (for F) and -5x²+26x+24=0 (for G).
We can negate each quadratic:
4x²-29x-24=0=(4x+3)(x-8), so it takes 8 seconds for F to hit the ground; 5x²-26x-24=0=(5x+4)(x-6), so it takes 6 seconds for G to hit the ground. G hits the ground 2 seconds before F, that is, F hits the ground 2 seconds after G, answer A.