Algebra practice question

Answer: 3

r = s + 4 and 2r + 3s = 23 give 2s + 8 + 3s = 23, so 5s = 15 and s = 3.

Common wrong answers

If you answered 5

5 comes from 5s = 23 − (−2), a sign error with the 8.

If you answered 7

7 is Ren's age.

If you answered 4.6

4.6 divides 23 by 5, ignoring the 8.

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