Question

Evaluate functions

w(n)=n^2-3n; find w(6)
h(n)=2n; find h(5)
h(x)=x^2+4x; find h(-7)

Answer 1

just substite 6,5, or -7 for n,h, or x then solve like a normal equation:
=6²-3(6)
=2×5
=(-7)²+4(-7)