algebra
posted by billy on .
A music concert was attended by 450 people. Adult tickets sold for $70 and childrenâ€™s tickets for $40. If total sales were $27,750, how much of each ticket was sold?

A = 450  C
70A + 40C = 27750
Substitute 440C for A in second equation and solve for C. Insert that value into the first equation and solve for A. Check by inserting both values into the second equation.