Given: angle 1 and angle 2 are supplementary, and angle 2 and angle 3 are supplementary. Prove: angle 1= angle 3

By definition of supplementary angles, m angle 1+ m angle 2=(a) and m angle 2+ m angle 3=(b). Then, m angle 1+ m angle 2=m angle 2 + m angle 3 by the (c).
Subtract m angle 2 from each side. You get m angle 1=(d), or angle 1=(e).

Answer is in the photo. I couldn't attach it here, but uploaded it to a file hosting. link below! Good Luck!

cutt.ly/XzW3SUN

set each factor equal to 0

4x-3 = 0

2x-1 = 0

solve for x.

4x-3=0

4x=3

x= 3/4

solve for x. 

2x-1= 0

2x= 1

x= 1/2

eventually after a few more steps, your answer should be 1/2 is less than or equal to x and 3/4 is greater than or equal to x