Given a triangle ABC, in which AB = 6 cm, AC = 10 cm. On its sides points are taken: M belongs to AB
Given a triangle ABC, in which AB = 6 cm, AC = 10 cm. On its sides points are taken: M belongs to AB, N belongs to BC, K belongs to AC. It is known that AMNK is a rhombus. Find the perimeter of the diamond.
Since AMNK is a rhombus, AM = MH = NK = AK.
Let the length of the side of the rhombus be X cm, then H = X cm, BM = (6 – X) cm.
In a rhombus, opposite sides are parallel, MH is parallel to AK.
Then the triangles ABC and BMH are similar in two angles, the angle B of the triangles is common, the angle BAC = BMH as the corresponding angles at the intersection of parallel lines AC and ML secant AB.
From the similarity of triangles:
MH / AC = BM / AB.
X / 10 = (6 – X) / 6.
6 * X = 60 – 10 * X.
16 * X = 60.
X = 60/16 = 3.75 cm.
Then Ravsd = 4 * 3.75 = 15 cm.
Answer: The perimeter of the rhombus is 15 cm.