solve quadratic equation by factoring how do you do it 3k^2 + 72 = 33k

Suppose your school costs for this term were $4900 and financial aid covered 3/4 of that amount. how much did financial aid cover? and how much do you still have to pay?

Two variables, x and y, vary inversely, and x=12 when y=4. what is the value of y when x=3?

When you have 25 numbers, and jake picks 3 random numbers and puts them back, what is the chance bob has of picking those 3 numbers when he picks 6 random numbers (without putting them back)? explain.