Complementary Angles When the sum of two angles is 90°, the angles are called complementary angles. Each angle is called the complement of the other angle. In the figure given below, ∠AOB + ∠BOC = 90° ⇒ 20° + 70° = 90°. Thus, ∠AOB and ∠BOC are complementary angles. Supplementary Angles

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Has two pairs of adjacent sides that are equal length. Diagonals are congruent. One pair of opposite angles are congruent. 1 diagonal creates 2 isosceles triangles when it goes from side to side. 1 diagonal creates 2 congruent triangles when it goes from top to bottom. 1 diagonal bisects angles.

Solution Verified by Toppr Given, cyclic quadrilaterals ABCD. and ∠A:∠C=5:4. Let the ∠A=5x, ∠B=4x. We know, in a cyclic quadrilateral, the sum of opposite angles are supplementary, i.e. 180o. Then, ∠A+∠C=180o 5x+4x=180o 9x=180o x=20o. Now, ∠A=5x =5×20o =100o. Hence, ∠A=100o. Was this answer helpful? 0 0 Similar questions

When we add or subtract angles, the result is called a compound angle. For example, \ (30^\circ + 120^\circ\) is a compound angle. Using a calculator, we find: \ [\sin (30^\circ +.