Advanced Math practice question

Answer: 27

The difference of squares factors as (sum)(difference): a² − b² = (a + b)(a − b) = 9 × 3 = 27. (The numbers are 6 and 3: 36 − 9 = 27.)

Common wrong answers

If you answered 6

6 is 9 − 3, which is not the difference of the squares.

If you answered 12

12 is the sum of 9 and 3, not their product.

If you answered 81

81 is 9², the square of the sum.

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