Please help me, I don’t understand!!

F(x) also means substitute the x
Not rly sure about g(x) but a teacher told me it is almost the same because it is just substitute.
F(x)=2x^2+6x-8
G(x)=-3x-3
So substitute 1 to the x’s
2(1)^2+6(1)-8
-3(1)-3
I will solve the first one first then next
2(1)^2+6(1)-8
First multiple
2+6-8
Next just solve that
ANWSER ONE IS ZERO
Next
-3(1)-3
Multiple
-3-3
Just solve it
ANWSER TWO IS -6