Advanced Math practice question

Answer: 1

Set the expressions equal: x² = x + 6, so x² − x − 6 = 0, which factors to (x − 3)(x + 2) = 0, giving x = 3 and x = −2. Their sum is 3 + (−2) = 1. The trap is adding the y-values or forgetting the negative solution.

Common wrong answers

If you answered 3

That's just one of the two solutions. The equation x² − x − 6 = 0 also gives x = −2, and the question asks for the sum: 3 + (−2) = 1.

If you answered 13

You added the y-values (9 and 4) instead of the x-values. The x-values are 3 and −2, and their sum is 1.

If you answered -1

You flipped the signs of the roots: (x − 3)(x + 2) = 0 gives x = 3 and x = −2, not −3 and 2. Their sum is 1.

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