Question

Write the equation of the circle with center (−3, 2) and (6, 4) a point on the circle.

Answer 1

So the general equation is

\(x^2+y^2=r^2\)

You want to add/subtract to the x to move it horizontally and add/subtract to the y value to move it vertically

You want to move the x and y so that it is focused on the center (In this case, 3 to the left of y and 2 up) Moving is counterintuitive so you add 3 and subtract 2

\((x+3)^2+(y-2)^2=r^2\)


To find the r value, find the distance between both points and solve


Once you have the radius (which should be ~9.2)

You should get 85

So your equation should be

\((x+3)^2+(y-2)^2=85\)


Answered solely because you were offline.