Question

In a ABC, D and E are points on side AB and AC respectively such that DE BC and AD:DB = 3:1. If AE = 3.3cm. Find AC.

Answer 1

Given AD/BD=3/1

Using Basic proportionality theorem, In a triangle a line is drawn parallel to one side of a triangle and intersect the other two side at distinct points, the other two sides are divided in the same ratio.

In ΔABC⇒

BD

AD

=

EC

AE

⇒

1

3

=

EC

6.6

⇒EC=2.2

Now AC=AE+EC

AC=6.6+2.2=8.8 cm