It is given that the circle is tangent to the y axis and has a radius of three units. This implies that the x-coordinate is 3 or -3.

The center lies in the third quadrant. So x = -3

The center also lies on y - 2x = 0

=> y + 6 = 0

=> y = -6

The center of the circle is (-3, -6).

**The product of the coordinates of the center is -3*-6 = 18.**