Build a Variable Expression for the Given Phrase

question 156

Multiple Choice

Build a variable expression for the given phrase.
-The difference between four times a number and nine

• A) 4 - x + 9
• B)4(x - 9)
• C) 9 - 4x
• D) 4x - 9

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Definitions:

Bacteria

Microscopic, single-celled organisms that exist in vast numbers in every environment on Earth, both harmful and beneficial.

Viruses

Infectious agents that replicate only inside the living cells of other organisms, causing various diseases.

White Blood Cells

Immune system cells that defend the body against infectious diseases and foreign substances.

Histamine

A compound found in the body as a part of the immune response that causes dilation of capillaries, contraction of smooth muscle, and stimulation of gastric acid secretion, involved in allergic reactions.