Question

solve this question 10

Answer 1

/_GEC=180- /_ECD
/_GEC=180-100
/_GEC=80°

/_FEB=180-/_ABE
/_FEB=180-120=60°

/_BEC=180-/_FEB-/_GEC
x=180-60-80
x=40°

Answer 2

First extend point B to T
then <DCE is equal to <BTE =100°
similarly <ABT is a straight line
Since <ABE + <TBE =180
So 120+<TBE=180
<TBE=180-120
<TBE=60°
Now by angle sum property of triangle
<TBE+<BET+<BTE=360°
60°+X°+100=360°
160°+X°=360°
Now <X°=360°-160°
<X°=200°