16Hit1600
Advanced MathEasy–MediumConstant from a conjugate product

Advanced Math practice question

When (x + 7)(x − 7) is written as x² − k, what is the value of k?

Answer: 49

(x + 7)(x − 7) = x² − 49.

Common wrong answers

If you answered 7
7 copies the number in the factors.
If you answered 14
14 adds 7 and 7.
If you answered -49
−49 has the sign wrong for k.

More Advanced Math questions

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