maths C2 doubt

[halosh92]

The points R(-2,5) S(2,1) T(-6,1) lie on the circumference of a circle. Find the equation of
RS and RT and hence find the coordinate of the centre of the circle
??

[astarmathsandphysics]

Method shown here

https://studentforums.biz/index.php/topic,5560.0.html

[halosh92]

Method shown here

https://studentforums.biz/index.php/topic,5560.0.html

there is the method of the perpendicular bisector method could you explain it perpendicular bisector wise?

[astarmathsandphysics]

Sorry saw three points and thought simultaneous eqs. When I get home

[astarmathsandphysics]

R(-2,5) S(2,1) T(-6,1)
RS gradient =(1-5)/(2--2)=-1
Y=-X+C
5==--2+c c=3
Y=-X+3
RT gradient =(1-5)/(-6--2)=1
y=x+c
5=-2+c c=7
y=x+7

[astarmathsandphysics]

Hence lines are at right angles with the right angle at R

hence St is a diamter
ST=sqrt((-6-2)^2+(1-1)^2)=8
radius =8/2=4
centre at(S+T)/2=((2,1)+(-6,1))/2=(-2,1)

[halosh92]

Hence lines are at right angles with the right angle at R

hence St is a diamter
ST=sqrt((-6-2)^2+(1-1)^2)=8
radius =8/2=4
centre at(S+T)/2=((2,1)+(-6,1))/2=(-2,1)

thx alot!