Vertical stretch, what exactly is it..

Question

anonymous · Answer

I was looking at y=x^2 and y=2x^2, how come i feel like 2x^2 has been compressed?

zepdrix · Answer

each x value you plug into 2x^2, will be twice as large as the same x value plugged into x^2, yes? :D
So the height of the graph will be increasing twice as fast.
What that looks like on a graph, is if you took a parabola and pinched the sides, to make it skinnier (growing faster).

anonymous · Answer

so the vertical stretch is saying the y being enlarged while x stays the same?

anonymous · Answer

and horizontal stretch is saying x is enlarged while y stays the same?

anonymous · Answer

so will it be easier if i just look at the slope for the graphs... i feel like these things are so confusing

zepdrix · Answer

"so the vertical stretch is saying the y being enlarged while x stays the same?"
Yes, good way to interpret it!

"and horizontal stretch is saying x is enlarged while y stays the same?"
I don't like the wording of this so much,
While it's true, our function is given as a function of X, not Y.
So I think it would be difficult to visualize Y holding it's same values as we move along the X axis, it just doesn't work quite right D:

the slopes? hmm

zepdrix · Answer

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