Algebra practice question

Answer: -10 or −10

5(x − 2) = 5x − 10. For the two sides to match for all x, k must be −10.

Common wrong answers

If you answered 0

0 would give 5x − 10 = 5x, which is never true.

If you answered 10

10 has the wrong sign; 5 × (−2) = −10.

If you answered -2

−2 forgets to multiply by 5.

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