Question

The Vertical angle of an isosceles triangle is 80 degree find measurement of its base angle

Answer 1

see the isosceles triangle has 2 side equal..
then the equation is like that

(80 +80 + x) =180
160+ x = 180
x = 180 -160
x = 20°

Answer 2

    an isosceles triangle means a triangle which has its base angles equal measured

     A vertical angle is  80 °

    Let that another angle = x

    Sum of angle of triangle is 180 °

              so x + 80 + 80 = 180°

                x = 180 - 160

               x  = 20 °

                x = 20 °

   Therefore the measure of base angle of given isosceles triangle is 20 ° . 


    

 I hope it is more easier to clear your doubt !!!!!!!!!