In parallelogram ABCD O is the intersection point of the diagonals. BD = 12cm, AD = 8cm

In parallelogram ABCD O is the intersection point of the diagonals. BD = 12cm, AD = 8cm, AO = 7cm. find the perimeter of the BOC triangle.

Because the diagonals of the parallelogram are divided in half by the intersection point, then CO = AO = 7 cm and BO = DO = 12/2 = 6 cm.The opposite sides of the parallelogram are equal: AD = BC = 8 cm.The perimeter is the sum of the lengths of all sides, which means the perimeter of the triangle BOC = BO + CO + BC. Perimeter BOC = 6cm + 7cm + 8cm = 21cm.