A truck that can carry no more than 6900 lb is being used to transport refrigerators and upright pianos. Each refrigerator weighs 300 lb and each piano weighs 475 lb. Write and graph an inequality to show how many refrigerators and how many pianos the truck could carry. Will 10 refrigerators and 10 pianos overload the truck? Explain. Help, I'm so confused because I dont have my notes.