The center of a circle is on the line y =2x and the line x=1 is tangent to the circle at (1, 6).
find the center and radius of the circle.

Step-by-step explanation:

slope of line perpendicular to x=1 is zero

eq. of line perpendicular to x=1 passing through (1,6) is

y-6=0(x-1)

or y-6=0

or y=6

to find the point of intersection of y=6 and y=2x

2x=6

x=3

so center is (3,6)

radius=√[(3-1)²+96-6)²]=2