In an isosceles triangle ABC, angle C is obtuse, angle A = 27 degrees. Find corner B.

Consider a triangle ABC.

Since, according to the problem statement, it is isosceles, the angles at its base are equal.

According to the condition of the problem, the angle C is obtuse, i.e. its degree measure is greater than 90 °, which means that the angle at the base of an isosceles triangle cannot be such an angle, since the second angle at the base will then be obtuse, and there cannot be two obtuse angles in the triangle, since the sum of their degree measures will be greater 180 °.

Therefore, we can conclude that angle B is the angle at the base of an isosceles triangle, and it is equal to the angle A = 27 °.

Answer: angle B = 27 °.