in a quadrilateral ABCD, angle ABC=40 degrees, angle BCD=100 degrees and angle CDA= 60 degrees. E is a point BC such that AE bisects the angle BAD. Find the size of the angle AED if angle BCA=44 degrees
thanx
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in a quadrilateral ABCD, angle ABC=40 degrees, angle BCD=100 degrees and angle CDA= 60 degrees. E is a point BC such that AE bisects the angle BAD. Find the size of the angle AED if angle BCA=44 degrees
thanx
3 diagrams to illustate
Internal angles in a quadrilateral add up to 360
So angle DAB = 160
This is bisected by line to E so
angle DAE = angle BAE = 80
From second diagram angle DAC = 180 - 60 - 56 = 64
angle CAE = angle DAE - angle DAC = 80 - 64 = 16
angle AEC = 180 - 16 - 44 = 120
Thinking of rest
Stuck on rest. Needs either angle ADE or angle DEC or angle BED
If length of AB = length of AD I have an answer
New diagram
Call the point where the lines cross in the centre F
angle ADE = 100 - X
angle DEC = 120 - X
angle CFE = X + 16 = angle AFD
angle CDE = X - 40
angle DFC = 164 - X = angle AFE
If we can find a numerical value for any of these angles we have solved it