Respuesta :

Hey

> Diagonals of a Rhombus Bisects the Angles at the Vertex

=> For a vertice holding an angle 120°, the Bisected Angle = 60°

Further, the Angle at the Second Vertice = 60°

Hence, we have an Equilateral Triangle with two sides as 10cm and the third - a diagonal

=> By definition of an Equilateral Triangle, Diagonal = 10cm