Factor Completely $$x ^ { 2 } + 4 x - 21$$

question 99

Multiple Choice

Factor completely. If the polynomial cannot be factored, write ʺprime.ʺ
- $$x ^ { 2 } + 4 x - 21$$

• A) \(( x - 21 ) ( x + 4 )\)
• B) \(( x - 7 ) ( x + 3 )\)
• C) \(( x + 7 ) ( x - 3 )\)
• D) Prime

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Definitions:

Glycerinated Muscle Fibers

Muscle fibers treated with glycerol to remove cellular contents while preserving the structure, used in experiments to study muscle contractions.

ATP

Adenosine triphosphate, a molecule that carries energy within cells for metabolism.

Slow-oxidative Fibers

Muscle fibers that contract slowly and are highly resistant to fatigue, relying on aerobic respiration to provide energy for prolonged activities.

Mitochondria

Organelles that serve as the powerhouses of the cell, generating ATP through the process of cellular respiration.