Question

. f(x) = 2x-5; Find f(-8)

Answer 1

You have just place the -8 into the f(x) so like this.
f(-8)=2x-5. then you solve it if x is -8 you do this next.
f(-8)=2(-8)-5, then you solve the two step equation.
f(-8)= -16-5
f(-8)= -21