The area of a rhombus is 300 cm². If the length of one of the diagonals of the rhombus is 30 cm, then what is the length (in cm) of the second diagonal?

20

We know that,

The area of a rhombus = \(\frac{1}{2}\) × (diagonal)1 × (diagonal)2

We have,

The area of rhombus = 300 cm²

The length of one of the diagonals of the rhombus = 30 cm 

So,

= 300 = \(\frac{1}{2}\) × 30 × (diagonal)2

= (Diagonal)2 = \(\frac{300}{12}\) = 20 cm