What is the effect on the graph of f(x)=2x+1 when g(x)=8f(x)?

Question

A The slope of the graph of g(x) is 8 times the slope of the graph of f(x). The y-intercept changes from 1 to 8.

B The slope of the graph of g(x) is 8 times the slope of the graph of f(x). The y-intercept does not change.

C The graphs of g(x) and f(x) have the same slope.

D The graphs of f(x) and g(x) have the same y-intercept.

Answer 1

The answer is A, since you're multiplying the whole function f(x) by 8.

Answer 2

f(x)=2x+1

g(x)=8f(x)=8(2x+1)=16x+8

Write both like: y=mx+b where m is the slope and b is the intercept

y_1=2x+1

y_2=16x+8

It is clear that y_2 slope is 8 times the slope of y_1 and y_2 intercept changes from 1 to 8. A is correct answer