OAR OAR Math Skills: Algebraic Expressions 5 — Questions and Answers
Question 1: What is the coefficient of x² in the expression 7 - 3x² + 4x?
- -3 (Correct answer)
- 4
- 7
- 3
Correct answer: -3
The coefficient of x² is the number multiplied by x², which is -3.
Question 2: Simplify: (2x²y)(3xy³)
- 6x³y⁴ (Correct answer)
- 6x³y³
- 5x³y⁴
- 6x²y⁴
Correct answer: 6x³y⁴
Multiply coefficients (2×3=6) and add exponents: x^(2+1)=x³, y^(1+3)=y⁴.
Question 3: Which expression equals zero when x = 3?
- x² - 2x - 3 (Correct answer)
- x² + 2x + 3
- x² - 9x
- x + 3
Correct answer: x² - 2x - 3
(3)² - 2(3) - 3 = 9 - 6 - 3 = 0.
Question 4: Translate to an algebraic expression: 'the product of 4 and a number x, decreased by 9'
- 4x - 9 (Correct answer)
- 4 + x - 9
- 9 - 4x
- 4(x - 9)
Correct answer: 4x - 9
'Product of 4 and x' is 4x; 'decreased by 9' means subtract 9, giving 4x - 9.
Question 5: Simplify: x⁰ + 3x¹ - 2
- 3x - 1 (Correct answer)
- 3x + 1
- 3x - 2
- 3x
Correct answer: 3x - 1
x⁰ = 1, so 1 + 3x - 2 = 3x - 1.
Question 6: What is the sum of 4x² - 3x + 1 and 2x² + 5x - 4?
- 6x² + 2x - 3 (Correct answer)
- 6x² - 2x - 3
- 6x² + 2x + 5
- 2x² + 2x - 3
Correct answer: 6x² + 2x - 3
Add like terms: (4+2)x² + (-3+5)x + (1-4) = 6x² + 2x - 3.
Question 7: If 2(x + 4) = 3(x - 1), what is x?
- 11 (Correct answer)
- 5
- 7
- 3
Correct answer: 11
2x + 8 = 3x - 3, so 11 = x.
OAR OAR Math Skills: Algebraic Expressions 5
What is the coefficient of x² in the expression 7 - 3x² + 4x?