Question

If ∠ABC=63°, find the measures of the unknown angles.

Answer 1

Answer:

Step-by-step explanation:

∠ABE + 77° + 78° = 180°                          [Angle Sum Property]

∠ABE + 115° = 180°

∠ABE = 180° - 115°

∠ABE = 65°

∠DEB + 77° = 180°                     [Linear Pairs]

∠DEB = 180° - 77°

∠DEB = 103°

∠BCD + 63° + 120° + ∠DEB = 360°  [Angle Sum Property Of Quadrilateral]

∠BCD + 63° + 120° + 103° = 360°

∠BCD + 286° = 360°

∠BCD = 360° - 286°

∠BCD = 74°