 Krishna
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Step 1: Find the angle   \angle ABC

NOTE: From the figure two angle forming the straight line

\angle ABC   = 180 - 116

= 64

Step 2: Find all the unknown interior angles of the isosceles triangles ABC

Skill 1: Know about the interior angle of isosceles triangles.

NOTE: Sum of the interior angles of the

isosceles triangle = 2 * (equal angle) + angle = 180 \degree

Skill 2: Set up an equation equating 180°

EXAMPLE: \triangle ABC is an isosceles triangle and

therefore \angle CAB = \angle ABC = 64

Skill 3: Substitute the known angle and simplify for the unknown angles

2(64) + \angle ACB = 180

\angle ACB = 180 - 128

\angle ACB = 52

Step 3: Find the angle \angle DCE

NOTE: Vertical angles are equal

So, \angle DCE + \angle ACB = 52

Step 4: Find the angles in another isosceles triangle CDE

NOTE: \triangle CDE is an isosceles triangle

So \angle DCE = \angle CDE = 52

Step 5: Find the angle \angle CED

\angle CED =180 - ( \angle DCE + \angle CDE )

\angle CED = 180 - 52 - 52 = 76 \degree