Question

Someone please help me

In the function y+3=(2x)^2+1, what effect does the number 2 have on the graph, as compared to the graph of y=x^2?
A. It shrinks the graph horizontally to 1/2 the original width
B. It shrinks the graph vertically to 1/2 the original height
C. It stretches the graph vertically by a factor of 2.
D. It stretches the graph horizontally by a factor of 2

Answer 1

2 would be a stretching factor. The graph of x^2 rises by x^2 every time, where as this graph, it rises by 2x^2. Think of it like this. The first few terms of x^2 are 1,4,9 , but the first few terms of 2x^2 would be 4,16... you can see that is is rising faster.

Answer 2

thanks