Can someone please answer these questions apart from number 4
Answers
Step-by-step explanation:
Let the equation of circle be x²+y²+2gx+2fy+c=0
Circle is passing through points(3,2)( -1,-2) and (5,-4).
Therefore points must satisfied in the equation of circle of circle.
1)Put x=3,y=2
6g+4f+c+13=0........ equation 1
2)Put x=-1,y=-2
-2g-4f+c+5=0......... equation 2
3)Put x=5, y=-4
10g-8f+c+41=0......... equation 3
Now, Add equation (1)and(2)
4g+2c+18=0....... equation 4
Multiply eqn(1) by 2
12g+8f+2c+26=0........ equation 5
Add eqn (3) and (5)
22g+3c+67=0....... equation 6
Solving eqn 4 and 6,
we get g= -5/2 and c= 4
put g=-5/2 and c= 4 in eqn 1
we get, f= -1/2
Centre of the circle : (5/2,1/2)
c= 4
r=√g²+f²-c
= 5/2
Equation of circle is
x²+y²-5x-y+4 =0
Hope it helps.
Thanks