Problem
The equation \( y=10 x+15 \) models the amount of money \( y \), in dollars, that Jack earns shoveling snow for \( x \) hours. How many hours does Jack need to work to earn \( \$ 55 \) ?
Solution
Step 1 ：1. y=10x+15
Step 2 ：2. 55=10x+15
Step 3 ：3. x=4
