i don't understand what a horizontal or vertical stretching is of a graph.

Question

y=x^3

Find graph horizontally stretched by a factor of 4

and vertically stretched by a factor of 4

Answer 1

vertically? multiply it by 4 : y=4x^3

horizontally? divide x by 4

y=(x/4)^3

Answer 2

http://www.analyzemath.com/horizontalscaling/horizontalscaling.html

check me.