Question

Let f(x) = -4x + 7 and g(x) = 10x - 6, find f(g(x)).
-40x + 24

-40x + 31

-40x + 64

-40x + 70

Answer 1

its b

Answer 2

always start in the middle
\[f(g(x))=f(10x-6)\]i.e. replace \(g(x)\) by \(10x-6\)

Answer 3

then where you see an \(x\) in \(f(x)\) replace that by \(10x-6\)
i.e.
\[f(\spadesuit)=-4\spadesuit +7\] so
\[f(10x-6)=-4\times (10x-6)+7\] then some algebra to clean it up

Answer 4

you get
\[-4(10x-6)+7=-40x+24+7=-40x+31\]

Answer 5

Thank you so much for explaining! I get it know! :)

Answer 6

yw