how would i solve this?

Set up an equation that describes the relationship between the two variables in the following situation. Graph that relationship. A manufacturer makes two types of products. Prot on Product A is $40 per unit, while prot on Product B is $50 per unit. Budgeted monthly prot is $5000. Let x be the number of units of ProductA sold, and let y be the number of units of Product B sold. Set up an equation that describes the relationship between the two variables