Algebra practice question

Answer: B. 7

Undo the operations in reverse order. Add 8 to both sides: 5x = 35. Divide by 5: x = 7. Check: 5(7) − 8 = 35 − 8 = 27.

Why the other answers are wrong

A. 3.8

You subtracted 8 instead of adding it: (27 − 8)/5 = 3.8. The equation has −8, so undoing it means ADDING 8.

C. 35

35 is 5x, one step from the answer. Divide both sides by 5 to isolate x.

D. 175

175 is 35 × 5 — you multiplied by 5 instead of dividing. To undo the 5 that multiplies x, divide.

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