Find the value of r(q(4)).

Question

Find the value of r(q(4)).

q(x)=-2x-4

r(x)=-5x-4

Answer 1

q(x) = -2x - 4 implies

q(4) = -2(4) - 4 = -12

r(x) = -5x - 4 implies

r(-8) = -5(-12) -4 = 56

But we know q(4) = -12, so r(q(4)) = r(-12) which we just showed equals 56