Advanced Math practice question

Answer: 11

a² − b² = (a − b)(a + b). Dividing by (a − b) cancels it (allowed since a ≠ b), leaving a + b = 11.

Common wrong answers

If you answered 0

0 would mean a = −b, but then a² − b² = 0 and the fraction would be 0, not 11.

If you answered 121

121 is 11², squaring the result. The expression simplifies directly to a + b.

If you answered 5.5

5.5 halves 11; nothing in the simplification divides by 2.

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