Algebra practice question

Answer: C. 36

Multiply both sides by 4: x = 36. Choice A (2.25) comes from dividing 9 by 4 instead of multiplying — the wrong inverse operation.

Why the other answers are wrong

A. 2.25

You divided 9 by 4 instead of multiplying — since x is already divided by 4, you undo that by multiplying both sides by 4.

B. 13

You added 4 to 9. The 4 is dividing x, so the inverse operation is multiplication: x = 9 × 4 = 36.

D. 45

There's no single step in this equation that gives 45; multiply both sides of x/4 = 9 by 4 to get x = 36, and check it: 36/4 = 9.

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