Answer:
x=30 degrees
Step-by-step explanation:
there are 3theorems that can be used for this
vertical angle theorem: vertical angles congruent
triangle sum theorem: all angles in triangle add up to 180 degrees
straight line?? i forgot the name: a straight line is 180 degrees
refer to image attached
measure of angle BAC is 36 degrees by vertical angle theorem.
look at the angle 105 degrees. it and a unknown degree to the left equal 180 because it makes a straight line. so measure of angle BDC is 180-105 degrees. measure of angle BDC is 75 degrees
then sum of all the angles in triangle ABD is 180
36 +(39+x) +75=180 degrees
solve equation
x +150=180
x=30 degrees
hope this helps !!
