The midpoints of sides , , and in are , , and , respectively. The medians drawn from , , and intersect the line segments , and at , , and , respectively. If the area of is sq cm, then the area, in sq cm, of is
The midpoints of sides , , and in are , , and , respectively. The medians drawn from , , and intersect the line segments , and at , , and , respectively. If the area of is sq cm, then the area, in sq cm, of is
Entered answer:
Solution
We have triangle ABC with area = 1440 sq cm. M, N, P are midpoints of sides AB, BC, AC respectively.
The medians of triangle ABC intersect triangle MNP at points X, Y, Z.
The trickest part of this question is getting the graph right. Post which, the solution is pretty simple.
When you connect the midpoints of a triangle's sides, you get the medial triangle.
The medial triangle has area = × (original triangle's area)
The medial triangle is similar to the original triangle with scale factor . Since area scales as (scale factor), we get .
Area of triangle MNP = sq cm
When the medians of a triangle intersect the sides of its medial triangle, the resulting triangle has area equal to of the original triangle's area. XYZ is nothing but the triangle from the median of MNP (hence, of MNP). It's like a shrunk up triangle of ABC.
This is a specific case that comes from the properties of medians and how they interact with medial triangles.
Area of triangle XYZ = Area of triangle ABC
Area of triangle XYZ = sq cm
Therefore, the area of triangle XYZ is 90 sq cm.