ACT · Pre-Algebra · Fractions, decimals, and integers
Question act-q-00235
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The question
If 9x − 9 = -18, what is the value of x?
- 0
- -2
- -1
- 1
Show answer & worked solution
Answer: -1
Worked solution. Subtract -9 from both sides: 9x = -9. Divide both sides by 9: x = -1.
Why each wrong choice is wrong. The off-by-one and negated answers are common arithmetic-slip distractors. Watch the sign of the constant term when you move it across the equals sign.
Test-day tactic. When the stem is short, do the algebra straight rather than plugging in answer choices — it's faster.
About this question type
Items test addition, subtraction, multiplication, and division of fractions and decimals; conversion between fractions, decimals, and percentages; and order of operations on mixed expressions.
You will see a question shaped like this one on roughly every other official ACT form, typically at a moderate position in the section — solidly within the range that separates a 600-band student from a 700-band student. Treat any miss in this subtopic as a signal to drill the subtopic page before you do another full practice test.