Question 190724
11.50x+7.50(12-x)=106
11.50x+90-7.5x=106
4x=106-90
4x=16
x=16/4
x=4 ans. for the number of compact discs bought.
Proof:
11.50*4+7.5(12-4)=106
46+7.5*8=106
46+60=106
106=106