Mathematics - Properties of Triangle Question with Solution | TestHub

At a vertex of angle $\theta$, the chord between its two contact points is 2r cos($\theta$/2). The tangent triangle is a 3-4-5 right triangle, so $\sum cos$ $\theta$=3/5+4/5+0=7/5. Thus the sum of squared chords is $4r^2$$\sum co{s}^2$($\theta$/2)=$2r^2$(3+7/5)=$44r^2$/5, not among A-C.