Question

http://www.rmes.us/AngelUploads/Content/MAT201//_assoc/Content/G%20Images/u2m3q3.jpg
Use the Interior Angle Sum Conjecture to find the measure of angle b?
A) 85°
B) 75°
C) 100°
D) 105°

Answer 1

please help!

Answer 2

b=105

Answer 3

lies on the same line as the denoted angle 105, against a line which is parallel to the line creating the 105 degree angle shown.

to satisfy your IASC req, note that the angle next to the shown 105 is 180-105=75, which there are two of.

then note that quadrilateral = 360 degrees.
therefore: 360-2(75)=2(x)
210=2(x)
105=x

your answer is D) 105