Advanced Math practice question

Answer: 15

The roots sum to 8 and differ by 2, so they are 3 and 5, and c is their product: 15.

Common wrong answers

If you answered 7

7 is a root of a different equation, x² − 8x + 7.

If you answered 12

12 gives roots 2 and 6, which differ by 4.

If you answered 16

16 would make the roots equal (both 4).

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