Agrocer mixed nuts worth 80 cents per pound with nuts worth 50 cents per pound. how many pounds of each did he use to make a minture of 30 pounds to sell at 75 cents per pound

To solve the system of equations below, pedro isolated the variable y in the first equation and then substituted it into the second equation. what was the resulting equation? { 5y=10x {x^2+y^2=36