Question

Suppose

DK
is an angle bisector of △DEF.

a
Given: EK=2, FK=5, DF=10.
Find DE.

Answer 1

4 units

Explanation:

Angle bisector property says that an angle bisector of a triangle will divide the opposite side into two segments that are proportional to the other two sides of the triangle.

By angle bisector property,

`(EK)/(KF)=(DE)/(DF)\\ \\(2)/(5)=(DE)/(10)\\ \\DE=(2\cdot 10)/(5)=4\ units`