MPT College Algebra 1 — Questions and Answers
Question 1: Simplify the expression: (x² + 5x + 6) ÷ (x + 2)
- x + 3 (Correct answer)
- x + 2
- x + 1
- x + 4
Correct answer: x + 3
Factor the numerator: <br> x² + 5x + 6 = (x + 2)(x + 3). <br> Now, cancel out the (x + 2) term in both the numerator and denominator: <br> (x + 2)(x + 3) ÷ (x + 2) = x + 3.
Question 2: Solve for x: 3x - 7 = 2x + 5
- 12
- 7 (Correct answer)
- -12
- -5
Correct answer: 7
Subtract 2x from both sides: <br> 3x - 7 - 2x = 2x + 5 - 2x, so x - 7 = 5. <br> Next, add 7 to both sides: <br> x = 12.
Question 3: Solve for x: 2x² - 5x - 3 = 0
- x = 3, -1/2 (Correct answer)
- x = -3, 1/2
- x = 3/2, -1
- x = 1/2, -3
Correct answer: x = 3, -1/2
To solve the quadratic equation 2x² - 5x - 3 = 0, use the quadratic formula: <br> x = [-(-5) ± √((-5)² - 4(2)(-3))] / (2(2)). <br> Simplifying gives: <br> x = [5 ± √(25 + 24)] / 4 <br> x = [5 ± √49] / 4 <br> x = [5 ± 7] / 4. <br> Thus, x = (5 + 7)/4 = 12/4 = 3, or x = (5 - 7)/4 = -2/4 = -1/2.
Question 4: Which of the following is the graph of y = x² - 4?
- A parabola opening up with vertex at (0, 4)
- A parabola opening down with vertex at (0, -4)
- A parabola opening up with vertex at (0, -4) (Correct answer)
- A straight line
Correct answer: A parabola opening up with vertex at (0, -4)
The equation y = x² - 4 represents a parabola that opens upwards because the coefficient of x² is positive. The vertex is at (0, -4) because the equation is in the form y = x² + c, where c is the vertical shift.
Question 5: What is the value of f(x) = 2x³ - 5x² + 3 at x = 2?
- 1
- 3
- 5
- 7 (Correct answer)
Correct answer: 7
To find f(2), substitute 2 into the function: <br> f(2) = 2(2)³ - 5(2)² + 3 <br> = 2(8) - 5(4) + 3 <br> = 16 - 20 + 3 <br> = 7.
Simplify the expression: (x² + 5x + 6) ÷ (x + 2)