Digital PSAT Math Practice Question 220: Answer and Explanation

Question: 220

6a² + 8ab - 4ac is equivalent to which of the following expressions?

• A. a(3a + 4b + 2c)
• B. 2a(3a + 4b - 2c)
• C. 4a(a + b - 2c)
• D. 2a(3a - 4b + 2c)

Correct Answer: B

Explanation:

(B) First, begin by factoring out all common factors. 2a is a factor of all three terms, so it can be factored out, leaving you with 2a(3a + 4b - 2c). Alternatively, you could have redistributed the answer choices to eliminate choice (A), (C), and (D), which respectively equal 3a² + 4ab + 2ac, 4a² + 4ab - 8ac, and 6a² - 8ab + 4ac.