In triangle QRS , QR is equal to 8 and RS is equal to 5 Which expresses all possible lengths of side QS ?

For a triangle, the third side must be greater than the difference of the other two sides and less than their sum. Here, |8 − 5| = 3 and 8 + 5 = 13, so 3 < QS < 13. This matches choice A: QS is greater than 3 and less than 13.

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