Answer:
0 < t < 1.04 or t ∈ (0, 1.04)
Step-by-step explanation:
Solving in steps:
- 9.8 < 20 – 9.8t < 20
- 9.8 - 20 < -9.8t < 20 - 20 ⇒ subtract 20 from all sides
- -10.2 < -9.8t < 0 ⇒ divide all sides by -9.8, this changes inequality signs to reverse
- 0< t < 10.2/9.8
- 0 < t < 1.04 or t ∈ (0, 1.04)