Instead of doing your problem for you, I'll do a different one that is EXACTLY
like yours step by step, that you can use as a guide for solving yours:
The one I'll solve is this one:
Find an equation for the circle that goes through the points (2,12) , (-7,3), and (11,3)
The general equation of the circle is:
Substituting (x,y) = (2,12)
Substituting (x,y) = (-7,3)
Substituting (x,y) = (11,3)
The system to solve is this:
Subtract the first two equations:
2A+12B+C=-148
-[-7A+ 3B+C= -58]
Change signs in bottom equation
2A+12B+C=-148
7A- 3B-C= 58
---------------
9A+ 9B = -90
Subtract the first and third equations:
2A+12B+C=-148
-[11A+ 3B+C=-130]
2A+12B+C=-148
-11A- 3B-C= 130
----------------
-9A+ 9B = -18
Solve the system:
Add them term by term
9A+9B=-90
-9A+9B=-18
--------------
18B=-108
B=-6
Substitute in
9A+9B=-90
9A+9(-6)=-90
9A-54=-90
9A=-36
A=-4
Substituting in
2A+12B+C=-148
2(-4)+12(-6)+C=-148
-8-72+C=-148
-80+C=-148
C=-68
So the equation of the circle
becomes
Now do yours the EXACT same way.
Edwin