Respuesta :

Answer:

  • 100°

Step-by-step explanation:

∠AEC ≅ ∠BED as vertically opposite angles

  • m∠AEC = m∠BED = 1/2(mAC + mBD), angles between intersecting chords

Substitute values and solve for x:

  • 4x = 1/2(120 + 2x)
  • 4x = 60 + x
  • 3x = 60
  • x = 20

Find the measure of AEC:

  • m∠AEC = 4*20 = 80°

AED and AEC form a linear pair hence supplementary:

  • m∠AED = 180° - m∠AEC

Find the measure of ∠AED:

  • m∠AED = 180° - 80° = 100°