Answer:

Explanation:
In the question, we're given 
. Therefore, the measure of these two angles must be equal.
To find the value of 
, set these two angles equal to each other:

Add 26 and subtract 
 from both sides:

Divide both sides by 3:

Since 
 was labelled as 
, substitute 
 to find its measure:

You can also substitute 
 into the label of angle D as angle A is congruent to angle D for easier calculations (
).