Question

the Vertical angle of an isosceles triangle is 100 degree find its base angle

Answer 1

The base angles of an isosceles triangle are equal to each other
let, base angles be x
therefore,
x+x+100=180
2x=80
x=40
which is your answers

Answer 2

HEY MATE....✋
HERE'S THE ANSWER
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We know in isosceles triangle there is two sides of equal length
100+ x+ x=180
100+2x=180
2x=180-100
2x= 80
x= 80/2= 40° .....ans