Question

What is the solution to the inequality below?
X^2>=81

Answer 1

• Answer:

A. x ≤ - 9 or x ≥ 9

• Explanation:

x² ≥ 81

| x | ≥ 9

x ≥ 0 => x ≥ 9 => x ∈ [ 9 ; + oo)

x < 0 => x ≤ - 9 => x ∈ ( -oo ; - 9 ]

x ∈ ( -oo ; - 9 ] ∪ [ 9 ; + oo)