ABCD is a rhombus with each side of length 20 cm. Angle ABC and ADC measure 60∘ each. The length of the diagonal AC is :
Consider the rhombus ABCD
In Triangle ABE, sin 30=AE20 ⇒12=AE20 ⇒AE=10 cm
We know that, diagonals of a Rhombus bisect each other at right angles,
Hence, AC=2 AE ⇒AC=20 cm.