Answer:
6 √3
Explanation:
I think the question must be "the perimeter of a rhombus is 24cm" instead of "the diagonal of a rhombus is 24cm"
1. the rhombus has 4 sides of equal length
2. the diagonals bisect each other at right angle
length of other diagonal: (√6² - 3²) x 2 = (√27) x 2 = 3 √3 x 2 = 6√3