15 Four circles and with the same radius are drawn in the interior of triangle such that is tangent to sides and, to and, to and, and is externally tangent to and .
15 Apat na bilog at na may parehong radius ay inilabas sa loob ng tatsulok tulad na ay padaplis sa panig at, sa at, sa at, At ay panlabas padaplis na at .