Q4 of 31 Page 110

The sides of a parallelogram are 6 centimetres and 14 centimetres and the angle between them is 30°. What are the

lengths of its diagonals?

Let us draw a perpendicular from D on AB say DH ⇒ DH ⊥ AB



In Δ ADH,


DH = sin 30° × AD


(From table: sin 30° = 0.5)


⇒ DH = 0.5 × 6 cm


⇒ DH = 3 cm


Area of parallelogram = Base × Height


Area = 14 × 3 cm2


Area = 42 cm2


Area of parallelogram is 42 cm2.


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