Answer:
14
Step-by-step explanation:
The two given angles are opposite angles and opposite angles always have the same measure. Knowing this, we can construct the following equation:
7r+6=8r-8
Subtract both sides by 6
7r+6-6=8r-8-6
7r=8r-14
Subtract both sides by 8r
7r-8r=8r-14-8r
-r=-14
Divide both sides by -1
r=14
I hope this helps!
