Multiply. the question is in the picture.

Bring the fraction a/a-4 to a denominator of 16-a^2

The function show two sisters' savings account and the rate at which they plan to deposit money

I'm at a bookstore with $\$35$ in my pocket and a $20\%$-off coupon. what is the cost of the most expensive book i can buy with my money and the coupon? (assume that there are books of every possible price in the bookstore. it's a large bookstore! )