The measure of the unknowns angles are ;
1. 95 °
2. 30°
3. 86°
4. 130°
Exterior angle theorem states that the sum of two interior angles is equal to the opposite exterior angle.
This means if a and b are the interior angles and c is the exterior, then;
a + b = c
The exterior angle theorem applies to all the problems.
1. 45 + x = 140
x = 140 - 45 = 95
2. x = 110 - 80
x = 30°
3. x = 28 + 58
x = 86°
4. x = 95 + 35
x = 130°