Hi all, I am struggling to finish this problem and was seeing if anyone could help me.

There are two circles.

Circle 1 has a center at (2,4), and radius 4.

Circle 2 has a center at (14,9) and radius 9.

I need to find the equation for common tangent line of these two circles. The circles touch so there is just one exterior tangent line.

Any help is appreciated, Thanks.