Question

in the adjacent figure a b is a straight line find the value of x hence find angle AOC and OD

Answer 1

Sum angles lying on a straight line ( Linear Pair of Angles) = 180 °

Angle AOC + Angle COD + Angle DOB = 180 °

( 3x - 7) °+ 55 ° + ( x + 20) ° = 180°

4x +68 ° = 180 °

4x = 180 ° - 68 °

x = 112 ° / 4

x = 28 °

ANGLE AOC = ( 3* 28 ° - 7) = 84 - 7 = 77°

ANGLE BOD = 28° + 20° = 48 °