how to draw a decagon ? its too hard....
A decagon is a polygon with ten sides and ten angles.
In order to construct a decagon, choose any 10 angles such that their sum is 360°.
Let us take the 10 angles as 36°, 36°, 36°, 36°, 36°, 36°, 36°, 36°, 36° and 36°.
Follow the given steps to construct the decagon.
Step1 : Draw a circle of any radius and centre O.
Step 2: Take a point A on the circle join OA.
Step 3 : Draw ∠AOB = 36° using a compass. Let the arm OB meet the circle in B.
Step 4 : Similarly, draw ∠COB = ∠DOC = .... = ∠JOA = 36° where, C, D, E, … J are points on the circle.
Step 5 : Join AB, BC, CD, …, IJ and JA.
∴ ABCDEFGHIJ is the required regular polygon.