5.25 - b ≥ 6.5
Solve for b:
5.25 - b ≥ 6.5
Subtract 5.25 from both sides:
-b ≥1.25
Multiply both sides by -1 ( and since you are multiplying by a negative you need to reverse the inequality sign as well).
b ≤ -1.25
Because the inequality sign contains equal to ( less than or equal to) the dot is solid and located at -1.25, because the inequality sign contains less than, the line/ arrow moves /points to the left.
The answer is the first one.