General Idea:
The Rules for Transformations of Functions are given below:
If f(x) is the original function, a > 0 and c > 0; Then


Applying the concept:
In the function y=5x^2-2, the effect that the number 5 have on the graph, as compared to the graph of y=x^2 is given below:
C.it stretches the graph vertically by a factor of 5