Determine the equation of the circle by the following information/transformation without graphing.
a.) A circle with centre (2,-3) and passing through (1,4) is reflecred in the x-axis.
So finding the centre is easy enough (x-2)^2 + (y-3)^2 = r^2
How do i find the radius though? If the point it passes through had the same x-value as the center then it would be a radius of 7. But it doesn't so how do i find this out?
Apparently the radius is square root of 50.
The equation is (X-2)sqr + (y+3)sqr = Rsqr-------------(1
But since the circle passes through (1,4) sub it into equation (1
so you get
(1-2)sqr + (4+3)sqr = Rsqr
1 + 7sqr = Rsqr
50 = Rsqr
R = 5Root 2
*** sqr = Squared
Always remember that if a line or any shape passes through a point, the equation must be satisfied when you sub that point into that equation. like what i did above
hope it helped
ask me if u have any further questions