Which quadratic equation passes through (5,12) and has a vertex (3,4)?

Iwant to know what 3g+5h+4g-2h is my teacher is too selfish to tell us

If y varies directly as x2 and y=6 when x=6, find the constant of variation.

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.