I need the inequality and solution

What is the result of adding the system of equations? 2x+y=4 3x-y=6

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! )

Which equation represents h for right triangle abc