Q7 of 9 Page 150

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 the angles that are equal be x°


Sum of angles of a Quadrilateral = 360°


x +x + 75° + 85° = 360°


2x + 160° = 360°


2x = 200°


x = 100°


Hence, each of the two equal angles is 100°


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