Raymond works in the shipping department of a toy manufacturer. Toy cars weigh 1 kilogram apiece and are shipped in a container that weighs 7 kilograms when empty. Toy trucks, which weigh 2 kilograms apiece, are shipped in a container weighing 5 kilograms. When packed with toys and ready for shipment, both kinds of containers have the same number of toys and the same weight. What is the number of toys? Simplify and put both into Slope Intercept Form.