Answer:
x∈[20/3;+∝).
Step-by-step explanation:
3x+10≥30; ⇔ 3x≥20; ⇔ x≥20/3
true
x=81 or 1/3
Option A for part A and $79 for part B
Answer: A
36
a² + b² = c²
a² + 77² = 85²
a² + 5929 = 7225
a² = 1296
a = 36