Answer:
$1.29x=10
Explanation:
You know that the goal is to reach 10 songs. So this number will go on one side of the equal sign. $1.29 is the amount to download a new song. Let x be the variable to mean each song. You are trying to find how many songs so you'd do: $1.29x/1.29=10/1.29 and x=7.75