*Use Pythag on triangle T1 C1 C2 to get T1 C2.*
True the angle at T1, is 90 degrees, but if I draw a hypotenuse from T1 to C2 then it will no longer be ninety. Then for this triangle T1 C1 C2 to become a right triangle, I would have to assume that the angle at C1 is 90 degrees, or am I just way off track here?

Mr F says: Quite right. mea culpa.
if I use the first method(since I don't know how to use the second one), I get the following equation

Mr F says: The first method is no good. See above.
and I don't know how to go on solving it from here.