Answer:
the answer is 4
Step-by-step explanation:
the angle between a side of a rectilinear figure and an adjacent side extended outward.
2.5
x=10,y=5,z=2
x+15=2x+5
x=10
4y=8y-20
4y=20
y=5
10z-5=3z+9
7z=14
z=2