The measure of the angles b and d, obtained using the same side interior angle theorem and linear pair property are;
13. m∠b = 60.7°, m∠d = 43.1°
The details of the steps by which the measure of the above angles are found are as follows;
The angle b and the 119.3° angle are same side interior angles formed between parallel lines, therefore, according to the same side interior angles theorem, we get;
119.3 + b = 180°
b = 180 - 119.3
b = 60.7°
The angle d is a linear pair angle with the 136.9° angle, therefore the angles d and the 136.9° angle are supplementary, and we get;
d + 136.9° = 180°
d = 180 - 136.9
d = 43.1°