a) The amount of money that a salesperson makes varies directly as the total amount of sales made. If the salesperson receives $7,500 for selling a hous for $120,000, how much will he or she make if he or she sells a house for $150,000?

b) Ifyvaries inversely asx^2, andy= 2 whenx= 4, what is the constant of variation?

I'm so confused with these problems. Please explain this to me as best as you can. Thanks!