A costume designer needs some silver and gold thread for the costumes for a school play. She needs a total of 240 yards. At a store that sells thread by the yard, silver thread costs $0.04 a yard and gold thread costs $0.07 a yard. The designer has $15 to spend on the thread. How many of each color should she get if she is buying exactly what is needed and spending all of her budget?

Write an equation for the length constraint. Write an equation for the cost constraint. solution