Question 524132
 Make a conjecture about the sum of the angles of a convex polygon with 'n' sides and use mathematical induction to prove your conjecture. 
----
Prove that an n sided quadrilateral 
has sum of interior angles = (n-2)180 degrees
------------------------------------------------------
Step #1: 
For n = 3, sum of angles = (3-2)180 = 180::::that is true
----
Step # 2:
Assume true for n = k sides, i.e, 
sum of interio angles = (k-2)180
-----
Step # 3:
Prove true for n = k+1 sides
----
sum for k+1 = sum for k sides + 180
sum for k+1 = (k-2)180 + 180
Factor out the 180 to get:
sum for k+1 = (k-2+1)(180)
Therefore, sum for k+1 sides = [(k+1)-2)]180
Q.E.D.