Find the obtuse angle of the rhombus if the perimeter is 8 cm and the height is 1 cm.

Given:
ABCD – rhombus,
Diamond perimeter = 8 cm,
CM = 1 cm,
Find: Angle A (obtuse angle)
Decision:
since AB = BC = AD = CD, therefore, BC = 1/4 of the perimeter of AВСD = 2 cm
Consider the MVS triangle:
CM = 1 cm, BC = 2 cm, therefore, the angle B = 30 degrees (since 1/2 of the hypotenuse lies opposite the angle of 30 degrees). Angle A = 180 degrees-30 degrees = 150 degrees.
Answer: 150 degrees