angle A + angle B = 180 degrees ... rhombus and h is the perpendicular distance between two parallelsides of the rhombus. ... The side length of the rhombus is equal to 10 feet. Find its area. ... A rhombus has 2 congruent opposite acute angles and two congruent ... area of rhombus = 2 (1 / 2) (10 feet) 2 sin (60 degrees)