What Is the sum 6x^2 + 2x - 4 and 2x^2 - 4x - 6

Ateacher has $80 to buy workbooks. each work book cost $3. if she buys as many workbooks as possible, how much money does she have leftover? a) $2 b) $4 c) $6 d) $8

If 30 lb of rice and 30 lb of potatoes cost ? $27.60? , and 20 lb of rice and 12 lb of potatoes cost ? $15.04? , how much will 10 lb of rice and 50 lb of potatoes? cost?

If 3 3/4 lb. of candy costs 20.25 how much would 1lb. of candy cost