Explanation:
domain: x-values
range: y-values
Graph 8:
domain: -2 ≤ x ≤ 4 (the lowest x-value is -2 and the highest is 4)
range: 0 ≤ y ≤ 6 (the lowest y-value is 0 and the highest is 6)
Graph 9:
domain: -∞ ≤ x ≤ 0 (the lowest x-value is negative infinity and the highest is 0)
range: -∞ ≤ y ≤ 0 (the lowest y-value is negative infinity and the highest is 0)