Two angles of a quadrilateral measure 85° and 75° respectively. The other two angles are equal. Find the measure of each of these equal angles.

Let x be the common angle of quadrilateral.


As per question,


A = 85°


B = 75°


C = D = x


As we know that, Sum of all four angles of quadrilateral is 360o.


A + B + C + D = 360°


85° + 75°+ x + x = 360°


2x = 360° - (85° + 75°)


2x = 200°


X = 200 / 2


= 100°


C = D = 100°


So, Two angles of quadrilateral whose measuring’s are equal is 100°.


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