Isosceles Triangle ABC: Calculate and Classify the 45° Vertex Angle

Question

Triangle ABC isosceles.

AB = BC

Calculate angle ABC and indicate its type.

Given that it is an isosceles triangle: $AB=BC$

It is possible to argue that: $BAC=ACB=45$

Since the sum of the angles of a triangle is 180, the angle ABC will be equal to:

$180-45-45=90$

Since the angle ABC measures 90 degrees, it is a right triangle.

90°, right angle.