Why does the slope intercept forumla use m and b.

For the given quadratic equation convert into vertex form, find the vertex and find the value for x=6 y=-2x^2+2x+2

Use the graph of the sine function y=2sinθ shown below

Last year, a state university received 3,560 applications from boys. of those applications, 35 percent were from boys who lived in other states. part a)how many applications did the university receive from boys who lived in other states? part b)applications to the university from boys represented 40percent of all applications. how many applications did the university receive in all? i don't how to do part b so me and plz tell how you got your answer