Answer:
12
Step-by-step explanation:
Total CD's Lisa bought = 15
Jazz music = 3
World music = x
Find x
Total CD's Lisa bought = Jazz music + World music
15 = 3 + x
Subtract 3 from both sides of the equation
15 - 3 = 3 + x - 3
12 = x
x = 12
Therefore,
World music = x = 12