Hello there!
Given F(x)=x-5 and G(x)=x^2 you want to find F(F(x)).
In order to do this, you don't need to know what G(x) is. Just put F into F...
F(x)=x-5
F(x-5)=x-5-5
F(F(x))=x-10
This is the question that you asked, but the photo makes it look like they want you to do G(F(x)) so I will do that one too.
G(x)=x^2
G(x-5)=(x-5)^2
THEREFORE...
G(F(x))=(x-5)^2
A is the answer!
EXPLANATION:
Remember that a function is like a machine. F(x) is a machine and G(x) is also a machine. Plugging F into G is basically taking the output of the F machine and putting it into the G machine.
I really hope this helps! If you need a more detailed explanation, feel free to message me.
BEST WISHES:)
