Answer:
[tex]r(x)=(4x)^7[/tex]
Step-by-step explanation:
For example,
If we wanted to horizontally compress [tex]y=x^2[/tex], we would multiply by 4 to get [tex]y=(4x)^2[/tex], and
if we wante to horizontally expand [tex]y=x^2[/tex], we would multiply by [tex]\frac{1}{4}[/tex] to get [tex]y=(\frac{1}{4}x)^2[/tex]
Since this question asks for horizontal compression, we multiply the [tex]x[/tex] of the function by 4. So the function we need is [tex]f(x)=(4x)^7[/tex]. The second choice is correct.