B=5a-4
pick any a valve and replace it with a you will get b
If the 3 points are collinear, then the slopes of all line segments connecting the points are the same.
Thus,
-6 - (-8) 2
m = ------------- = -------- = -1/2
-7 - (-3) -4
Then the following must be true:
4-(-6) 10
-1/2 = ------------ = ---------
c - (-7) c + 7
Cross multiplying, -(c+7) = 20, and c+7 = -20, so that c = -27
To figure out the degrees, you would create a ratio.
Since there are 360 degrees in your circle, that would be representative to 100 (because both are the total of what you want to find), and x would be representative to what degrees 65 is equal to.
your ratio should look like,
65/100=x/360
cross multiply and get
65(360)=100x
23400=100x
x=234
It looks hard to read like this, but if you write it out on your paper it should make more sense!
