Question 293167
let the dvd cost x

let the cd cost y

last month

5x+2y=65

this month

3x+4y =81

3(5x+2y)= 3*65

5(3x+4y)=5*81

18x+6y = 195

18x+20y=405

subtract the equations

-14y=- 210

y=-210/-14

y=15

By substituting the value of y in any equation we get x=7



x=7