Tangents, by definition, will be perpendicular to the radius lines meeting the circle at the point of tangency. Sosolveeach of the two tangent equations for "y=", and read off their slopes. Use this information tofind the valuesof the slopes of the radii.

In this case, the tangents are perpendidular, which means that they meet the circle at either end of a diameter line. Findthe equationofanyline perpendicular to the tangents. Find the points where this line crosses the two tangents.

Then plug these points intothe Distance Formulato find the length of the diameter.

Divide by "2" to find the length of the radius.