since the distance of the the two DE and CE is equal to the radius you can compare the two triangles BDE and CDE. since they have two equal sides and one shared side their third side must be equal as well leaving you with DE = CE 15y - 50 = 17y - 62 62 -50 = 17y - 15y 12 = 2y 6 = y Knowing that y=6 you can conclude that DE=CE=40mm Since BD and ED create a right angle (sane as CB and CD) you can use the pythagorean theorem to calculate BE BE^2= CE^2+CB^2 BE^2 = 30^2 + 40^2 BE^2 = 2500 BE = 50mm im not sure about the last question sorry