PSAT Math Multiple-Choice Practice Question 473

Correct Answer: C

Explanation:

C

Difficulty: Hard

Category: Completing the Square

Getting to the Answer: First divide both sides by 4, so that 4x² - 8x + 64 = 0 becomes x² - 2x + 16 =0. Notice that this cannot be solved by factoring, so use the completing the square method:

Therefore, (C) is correct.