For this case we have the following functions:

When composing the functions we have:

Substituting values we have:

Rewriting:

The function has a horizontal asymptote at y = 3.
Therefore, the range of the function is all reals minus y = 3.
Answer:
option 3
Answer:
x = -7
Step-by-step explanation:
f(x) = -2x + 9
f(x) = 23
therefore, f(x) =
-2x + 9 = 23
-2x = 23 - 9
-2x = 14
-x = 14 ÷ 2
-x = 7
x = -7
Last one is your answer
------------------------------
So you subtitute y=3x into
2x+y=15
so
2x+(3x)=15
add like terms
5x=15
divide both sides by 5
x=3
subtitute x=3 into first equation (y=3x)
y=3(3)
y=9