Area of a Quadrilateral within a Triangle

x coordinate of E

6.3

coordinates

solution

Let

ΔABC

be a triangle and let

E

and

F

be points on

BC

and

AC

, respectively. Let

D=AE⋂BF

. You can calculate the area of the triangle

|ΔABC|

by checking "coordinates" to find the base and height. You can drag the points

B

and

C

. Suppose that

|ΔADF|/|ΔABD|=3/7

and that

|ΔADF|/|ΔBDE|=3/7

.

What is

|ECFD|/|ΔABC|

? See Details for the solution.