Question

IF diagonals of a rhombus are 9cm and 12cm, find its sides?

Answer 1

it is 15
because the diagnols make an right angle triangle
so we can make the side as hypotheses and the diagnols as the height and base and then it can be solved by pythagoreaus theorum because 3, 4, 5 are pythagorian triplets thet are the 3rd multiple of 345

Answer 2

Let the rhombus be ABCD with its diagonals AC and BD meeting at O.
since diagonals bisect each other in a parallelogram,OA=OC=3cm and OB=OD=6cm
since diagonals intersect at right angles,in ΔAOB,∠O=90 degrees
there fore by pythagoras theorem
 $AB^{2}= OA^{2} + OB^{2}$
$3^{2} + 6^{2} = x^{2}$
9+36=45
x=√45=3√5cm
The side of the rhombus is 3√5cm