Help? If (g)x is a vertical stretch by a factor of 3 of f(x)=3x+1, what is the rule for g(x)

Question

If (g)x is a vertical stretch by a factor of 3 of f(x)=3x+1, what is the rule for g(x)

Answer 1

For a vertical stretch:

 

g(x) = a f(x), where a > 1

 

g(x) = 3 f(x)

g(x) = 3(3x + 1)

g(x) = 9x + 3

Answer 2

Only functions that are curves have stretches.  The function here is linear, which means that we will have a straight line. This line extends infinitely in both directions.