Solve the Inequality $$x ^ { 2 } - 4 x - 21 \leq 0$$

question 82

Multiple Choice

Solve the inequality. Write the solution set in interval notation.
- $$x ^ { 2 } - 4 x - 21 \leq 0$$

• A) \(( - \infty , - 3 ] \cup [ 7 , \infty )\)
• B) \([ 7 , \infty )\)
• C) \(( - \infty , - 3 ]\)
• D) \([ - 3,7 ]\)

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Definitions:

Ball And Socket

A type of synovial joint where a spherical head fits into a cup-like socket, allowing multidirectional movement and rotation.

Autoimmune Disease

A condition in which the immune system mistakenly attacks the body's own tissues.

Arthritis

Arthritis is a term for conditions that cause inflammation and stiffness in the joints, leading to pain and mobility issues.

Synovial Membrane

A specialized connective tissue that lines the inner surface of capsules of synovial joints and tendon sheath, making synovial fluid to lubricate and reduce friction.