Question

prove that the sum of the angle of a triangle is 180 degree if in triangle abc angle A + angle b is equal to 120 degree and Angle B + angle C is equal to 180 degree then find Angle B

Answer 1

HEY!!
THE ANSWER IS HERE,

In triangle, ABC

A+B+C=180........(1)

=> given that A+B=120

=> 120+C=180

=> C=180-120

=> C= 60.

And also given that, B+C= 180.

=> B+60=180

=> B=120.

substitute the value of B in equation (1) .

A+120+60=180

=> A+180=180

=> A=0

In triangle one angle is zero.so the triangle will not form with these angles.

:-)Hope it helps u.