If a = 3 and b = -2, what is the value of a² - 2ab + b²?

Answer and explanation

Correct answer: C. 25

  1. Step 1: a² = 9 and b² = 4. Step 2. -2ab = -2 × 3 × (-2) = +12. Step 3. 9 + 12 + 4 = 25, which is (a - b)² = 5². Answer: 25. Why not the others: 1: This uses a + b = 1 for the square, which does not match the expression. 13: This adds a² and b² only and leaves out the -2ab term. 17: This subtracts b² instead of adding it, giving 9 + 12 - 4.

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