Let the measure of an angle be "a"
let the supplement be "s"
a= s-23
        
             
        
        
        
Answer:
x=20
Step-by-step explanation:
These angles are vertical angles so they are equal.
7x-99 = 2x+1
Subtract 2x from each side
7x-2x -99 = 2x-2x+1
5x -99 =1
Add 99 to each side
5x-99+99 = 1+99
5x = 100
Divide each side by 5
5x/5 =100/5
x = 20