Question

In the
x
y
−
xy−
plane, the center of a circle has coordinates
(
6
,
10
)
(6,10)
and the circle touches the
y
−
y−
axis at one point only. What is the radius of the circle

Answer 1

I will interpret this as:

In the xy-plane, the center of a circle has coordinates
( 6,10) and the circle touches the y-axis at one point only. What is the radius of the circle.

If you make a sketch of the circle that has a centre of (6,10) and touches the y-axis, you can see that the radius has to be 6

It's equation must be (x-6)^2 + (y-10)^2 = 36