Δ ABC is an isosceles triangle with known angle a = 20 ° and angle B =?

Possibility 1:
The bottom corner is ab
Then the angle B is 20 degrees
Possibility 2:
The base angle is BC
Then the angle B is 80 degrees
Possibility 3:
The base angle is AC
Then the angle B is 140 degrees
In conclusion, the angle B is 20 °, 80 ° or 140 °
Do not understand, welcome to ask!
Thank you very much!

In triangle ABC, when angle a = 30 degrees and angle B = what, triangle ABC is isosceles triangle

When angle B = 30 or 75 degrees, triangle ABC is isosceles triangle

Mathematical problem! Isosceles triangle ABC, one of the angles is 100 degrees, then the other two angles are? Specific process!

The sum of the internal angles of a triangle is 180 degrees, so 100 degrees must be the top angle of the triangle, so 2x = 180-100, so the bottom angle X is 40 degrees

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