(180 - 78) / 2...
80 degrees.
If your "53" is in degrees, then the vertex angle is 74 degrees.
20 degrees and the two equal angles will be 80 degrees each
The total internal angles of a triangle always equal 180 degrees. Therefore, the third angle of this triangle must be 180 - 54 - 63 = 63. Since this value is the same as one of the stated sides, the triangle is indeed isosceles.
An isosceles triangle
130 degrees is the measure of the base angles of an isosceles triangle whose vertex has a measure of 50 degrees.
20 degrees
80 degrees
55 degrees
57.5 degrees
135 degrees.
The sum of all three interior angles of any triangle, isosceles or not, is 180 degrees.
44 degrees
If it is an isosceles triangle then the base angles must be equal angles of 69 degrees because there are 180 degrees in a triangle and 42+69+69 = 180 degrees
51 degees
(180 - 38)/2 = 71 degrees (base angles of an isosceles triangle are congruent).
The vertex angle of an isosceles triangle is equal to the measure of each of its base angles. Therefore, if one of the base angles measures 42 degrees, then the vertex angle also measures 42 degrees.