Joanna has a total of 7 rolls of coins worth $23. she has rolls of dimes worth $5 each, and rolls of nickel worth $2. how many rolls of each kind does she have?

What is the slope of the line passing through the points (-5, 7) and (-3,5)?

Huong is organizing paperback and hardback books for her club's used book sale. the number of paperbacks is 12 less than three times the number of hardbacks. huong had 162 paperbacks. how many hardback books were there?

You work for a landscape company that just got a contract to re-mulch a park. the area that needs mulching is 30 feet by 60 feet. they want a 3 inch layer of much on the area. the company has bags of mulch that cover 2 cubic yards that cost $4.00 per bag. how much will it cost the consumer just in materials to re-mulch the area (round to the nearest dollar)?