Advanced Math practice question

Answer: 10

(a + b)² = a² + 2ab + b². So 49 = 29 + 2ab, giving 2ab = 20 and ab = 10. (Indeed a and b are 2 and 5.)

Common wrong answers

If you answered 20

20 is 2ab. Divide by 2 for ab.

If you answered 22

22 is 29 − 7. The relation involves 49 = (a + b)², not 7 itself.

If you answered 36

36 is 29 + 7, adding the two given values. Use (a + b)² = a² + 2ab + b².

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