The vertical angle of an isosceles triangle is 100°. Find its base angles.

Consider an isosceles triangle ABC,

Such that:


AB = AC


Given,


Vertical A is 100o


To find: Base angle


Since, is isosceles,


B = C (Angle equal to opposite sides)


And,


A + B + C = 180o (Angles of triangle)


100o + B + B = 180o


B = 40o


B = C = 40o


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