Algebra practice question

Answer: -5 or −5

Substitute x = −2: −8 − 5k = 17, so −5k = 25 and k = −5.

Common wrong answers

If you answered 1

1 comes from 8 − 5k = 17 with the sign of 4x wrong for x = −2.

If you answered 5

5 has the wrong sign.

If you answered -1.8

−1.8 comes from −5k = 9, subtracting 8 from 17 instead of adding it.

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