[tex]\bf Step-by-step~explanation:[/tex]
Let's look at (a) first. Since -5 is in parenthesis, we have to replace x with -5. You do the same thing on (b): replace x with 2.
[tex]\bf Step~1~(a):[/tex]
We have to replace x with -5.
[tex]\bf f(x)=x^2-2x\\f(-5)=(-5)^2-2(-5)\\f(-5)=25-2(-5)\\f(-5)=25+10\\f(-5)=35[/tex]
[tex]\bf Step~2~(b):[/tex]
We have to replace x with 2 now.
[tex]\bf f(x)=x^2-2x\\f(2)=2^2-2(2)\\f(2)=4-2(2)\\f(2)=4-4\\f(2)=0[/tex]
[tex]\large\boxed {\bf Our~final~answer:~f(-5)=35; ~f(2)=0}[/tex]
