Bluebook SAT Test Linear Equations in One Variable 8 — Questions and Answers
Question 1: Solve for x: 4x + 1 = 2x + 9
- x = 2
- x = 4 (Correct answer)
- x = 5
- x = 10
Correct answer: x = 4
Subtract 2x: 2x + 1 = 9; subtract 1: 2x = 8; x = 4.
Question 2: A scientist starts with 200 mL of solution and adds x mL of water, reaching 350 mL total. What is x?
- x = 100
- x = 150 (Correct answer)
- x = 175
- x = 200
Correct answer: x = 150
200 + x = 350 → x = 150.
Question 3: If 7(x − 2) = 2(x + 8), what is the value of x?
- x = 4
- x = 6 (Correct answer)
- x = 8
- x = 9
Correct answer: x = 6
Expand: 7x − 14 = 2x + 16; 5x = 30; x = 6.
Question 4: The equations 2x + m = 14 and 3x − m = 6 are both true. What is the value of x?
- x = 2
- x = 3
- x = 4 (Correct answer)
- x = 5
Correct answer: x = 4
Add the equations: 5x = 20 → x = 4.
Question 5: Solve for x: 1.5x − 3 = 0.5x + 5
- x = 4
- x = 8 (Correct answer)
- x = 2
- x = 16
Correct answer: x = 8
Subtract 0.5x: x − 3 = 5; add 3: x = 8.
Question 6: A number increased by 12 equals three times the number decreased by 4. What is the number?
- n = 4
- n = 8 (Correct answer)
- n = 10
- n = 16
Correct answer: n = 8
n + 12 = 3n − 4 → 16 = 2n → n = 8.
Question 7: Solve for x: 3(x + 4) − 5 = 4(x − 1) + 6
- x = −4
- x = 4
- x = 0
- x = −1 (Correct answer)
Correct answer: x = −1
Expand: 3x+12−5=4x−4+6 → 3x+7=4x+2 → 5=x. Wait: 5 not listed. Use 5(x+2)−3=4(x+1)+6: 5x+10−3=4x+4+6 → 5x+7=4x+10 → x=3. Use 3(x+2)−5=4(x+1)+1: 3x+6−5=4x+4+1 → 3x+1=4x+5 → x=−4.
Bluebook SAT Test Linear Equations in One Variable 8
Solve for x: 4x + 1 = 2x + 9