Notice the picture below
now, if the arc "x" is 48°, and the arc across the circle is also 48°, then those chords are congruent, notice the chords in red
I don't know what c you are talking about because there is no picture
For this case we have that by definition, the point-slope equation of a line is given by:
Where:
m: It's the slope
It is a point through which the line passes
According to the statement data we have:
Substituting we have:
By law of signs of multiplication we have to:
Answer:
The requested equation is: 
I believe the answer is 8
The scale faction is 20 to 1 hope that helps
