IBEW Solving Linear Equations 2 — Questions and Answers
Question 1: Solve for x: 3x - 7 = 14
- x = 7 (Correct answer)
- x = 3
- x = 21
- x = 2
Correct answer: x = 7
Add 7 to both sides: 3x = 21, then divide by 3: x = 7.
Question 2: An electrician earns $28 per hour plus a $50 flat fee per job. If she earned $330 on a job, how many hours did she work?
- 10 hours (Correct answer)
- 12 hours
- 8 hours
- 11 hours
Correct answer: 10 hours
Set up 28h + 50 = 330, so 28h = 280, giving h = 10 hours.
Question 3: Solve for y: 5y + 3 = 3y + 11
- y = 4 (Correct answer)
- y = 2
- y = 7
- y = 1
Correct answer: y = 4
Subtract 3y from both sides: 2y + 3 = 11, then subtract 3 and divide: y = 4.
Question 4: If 2(x + 4) = 18, what is x?
- x = 5 (Correct answer)
- x = 7
- x = 9
- x = 3
Correct answer: x = 5
Divide both sides by 2: x + 4 = 9, then subtract 4: x = 5.
Question 5: Solve for x: x/4 + 6 = 10
- x = 16 (Correct answer)
- x = 4
- x = 24
- x = 64
Correct answer: x = 16
Subtract 6 from both sides: x/4 = 4, then multiply by 4: x = 16.
Question 6: A conduit requires two sections. One section is 3 feet longer than the other, and together they total 21 feet. How long is the shorter section?
- 9 feet (Correct answer)
- 12 feet
- 8 feet
- 10 feet
Correct answer: 9 feet
Let x = shorter; x + (x+3) = 21, so 2x = 18, x = 9 feet.
Question 7: Solve for n: -3n = 24
- n = -8 (Correct answer)
- n = 8
- n = -72
- n = 72
Correct answer: n = -8
Divide both sides by -3: n = 24 ÷ (-3) = -8.
