Help please. Can someone please show me how to work this out. I will give a medal.

Let f(x) = x - 2 and g(x) = x2 - 7x - 9. Find f(g(-1)).

-21
-3
3
21

Question

Help please.  Can someone please show me how to work this out.  I will give a medal.                  

Let f(x) = x - 2 and g(x) = x2 - 7x - 9. Find f(g(-1)).

-21
-3
3
21

bibby · Answer

g(-1) = (-1)^2 - (7*-1) -9
plug that into f(x)

hint: (-1)^2 = 1

anonymous · Answer

ok

anonymous · Answer

then what do I do?

bibby · Answer

There's nothing else to do.

g(-1) = (-1)^2 - (7*-1) -9
g(-1) = 1- (-7) - 9

Simplify that and plug it into f(x)

anonymous · Answer

oh ok

anonymous · Answer

I am sorry I am confused can you show me how to simply it so I can figure out the correct answer?

anonymous · Answer

I have never had a teacher that actually teaches math they just give you work to do and that is it.

bibby · Answer

Try not blaming the teacher. Just learn the math any way you can.

Why can't you simplify "1- (-7) - 9"?