Problema Solution
Select the set of equations that represents the following situation: The cost of two CDs and fifteen DVDs is $132.28; and the cost of fourteen DVDs and twelve CDs is $208.00. How much do a CD and a DVD cost?
Answer provided by our tutors
let x be the cost of 1 CD and y be the cost of 1 DVD
2x + 15y = 132.28
12x + 14y = 208.00
-12x - 90y = -793.68
12x + 14y = 208.00
_________________ add the equations
-76y = -585.68
y = $7.7063
2x + 15y = 132.28
2x + 15*7.70 = 132.28
2x = 16.6852
x = 8.3426