Answer:
The answer is D: 42
Explanation:
Angle 7 and angle 138 are supplementary and must add up to 180
Angle 7 is congruent to angle 6 through CPCTC (Corresponding Parts of Congruent Triangles are Congruent)
Angle 7 and 6 are corresponding angles
you must find angle 7 becasue Angle 7= Angle 6
angle 7=x
138-x=180
solve for equation you get
x=42
Angle 7 = 42
so that means that Angle 6 is 42