Write a profit formula for this mixture problem: A company manufactures patio chairs (x) and rockers (y). Each piece is made of wood, plastic, and aluminum. A chair requires one unit of wood, one unit of plastic, and two units of aluminum. A rocker requires one unit of wood, two units of plastic, and five units of aluminum. The company's profit on a chair is $7 and on a rocker is $12. The company has available 400 units of wood, 500 units of plastic, and 1450 units of aluminum. P