Very hard to Solve
Geometry
Level
pending
The triangle ABC is isosceles so that AB = BC and angle B = 20°. From angle C, the CD is drawn so that D is on AB and angle ACD = 50°. From angle A, AE is drawn so that E is on BC and angle AEC = 40°. Drag DE and determine the angle DEA.
Hint try to draw the triangle.
The answer is 30.
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1 solution
LED THREAD TO THE ANSWER. Draw a large triangle with angles as shown. Drag a line from A that intersects the EC on point F, so that angle AFC becomes 80°. Then draw FD. Take advantage of angle sets in several of the triangles that were formed. Some are isosceles and some equilateral triangles.