How to answer it
- Distribute and simplify.
- Isolate the variable with inverse operations.
- Substitute your answer back to check.
Worked example
An original question in the ACT format, already answered.
ACT MathWorked example
3(2x − 1) = 21
What is the value of x?
- A3
- B11/3
- C4
- D6
Answer: C. Distribute: 6x − 3 = 21. Add 3: 6x = 24, so x = 4. Choice B forgets to distribute the 3 to the −1.
The most common trap
Distributing to the first term only. The 3 multiplies both 2x and −1.
Practice it
Hourly Prep’s daily sets mix algebra with the rest of ACT Math, and send more of it your way when it’s a weak spot. See how the ACT prep plan works, or browse the other ACT skill guides.
For pacing and strategy across the whole section, read our 2027 ACT format guide. To fit this skill into a schedule, see the ACT study plan guide.