Answer:
Step-by-step explanation:
= 
Angle 15 and Angle 9 make a straight line
Answer:
x = 29
Step-by-step explanation:
I think this because they give you 78 degrees. The angle across from it (3x - 9) must equal 78 degrees as well. So solve as (3x - 9) = 78. 78 + 9 is 87. 87 divided by 3 is 29.
Hope it helps and is correct!
Infinite solutions; both equations are the same.
Hope this helps! <3
