ABC triangle, find angle C if angle A and B = 40 degrees.

Consider a triangle ABC.
In the indicated triangle, the values of two angles are given.
These are corners A and B.
In order to find out what the third angle is, recall the rule according to which the sum of all the angles of a triangle is 180 °.
Now let’s write down equality.
A + B + C = 180 °.
By condition, the angle A is equal to 40 °. Angle B is also 40 °.
In order to find the third angle, we substitute the values of the angles A and B into the above equality.
40 ° + 40 ° + C = 180 °.
80 ° + C = 180 °.
C = 180 ° – 80 °.
C = 100 °.
Answer: 100 ° is the value of the angle C.