Answer: x ≥ $30.
Where x is the amount of money that you need to spend if you want to have the 3 free songs.
Step-by-step explanation:
When you spend $45 or more, you get 3 free songs.
You already bought an album that costs $15, then the minimum amount that you need to spend is (when you spend exactly $45):
$45 - $15 = x = $30.
Then the inequality is:
x ≥ $30.
Because if you spend more than $45 you also get the songs.
