At a concert, you purchase 3 T-shirts and a concert program for a total cost of $90.The program for a total cost $15 and the T-shirts all cost the same. Write and solve an equation to find the cost of one T-shirt
T = (TC-C)/3 This equation will work out the cost of 3 t-shirts (subtracting the total cost by the cost of the program) then dividing it by 3 as they bought 3 t-shirts. Giving the cost of 1 t-shirt.