In a rhombus PQRS, and PQ = 18 cm, then the diagonal QS is: Alternate
B. 16 cm
C. 12 cm
D. 18 cm
Right Answer is: D
In this rhombus angle SPQ = 60o , therefore angle PQR and angle PSR will be equal to 120o (supplementary angles)
We know that diagnols of a rhombus bisects the angles, PSQ and angle PQS will be equal to 60o , and hence Triangle PQS will be an equilateral triangle. Hence, QS will also be 18 cm.