I am having trouble with this question.

Isee the amount was $90.00 then reduced to $75.00 , what is the percent ?

Acredit card advertises an annual interest rate of 23%. what is the equivalent monthly interest rate?

Lindsay used two points, (x,y; ) and (+2.82), to find the equation of the line, y = mx + b, that passes through the points. y2-y, first, she used the definition of slope and determined that the value of mis x, - . given this information, which expression must represent the value of b?