7. Answer: +4, x ≥ 16
Explanation:
x - 4 ≥ 12
Add 4 to both sides (to isolate the variable):
x - 4 + 4 ≥ 12 + 4
x ≥ 16
Graph has a closed dot with an arrow pointing to the right of 16.
16 ·------------→
9. Answer: x ≤ 9
Explanation:
x - 20 ≤ -11
Add 20 to both sides of the equation:
x -20 +20 ≤ -11 +20
x ≤ 9
Graph has a closed dot with an arrow pointing to the left of 9.
←----------· 9