Answer:
y = -3x + 60, D: x ≥ 0, r: y ≥ 0
Explanation:
1. Find the slope (x-axis is the week number, y-axis is the # of dump loads)
Slope equation: (y₁ - y₂)/(x₁ - x₂), where two points are (x₁, y₁) and (x₂, y₂)
Plug in: (45 - 30)/(5 - 10)
Subtract: 15/(-5)
Divide: -3, representing the number of dumps removed/week
2. Find the y-intercept (when x = 0)
Since we found that 3 dumps are removed per week, we can find that at week 0, there were 60 dump loads.
3. Construct equation
Point-intercept equation: y = mx + b, where m = slope, b = y-intercept
Plug in: y = -3x + 60 (with the domain of x ≥ 0 and the range of y ≥ 0)