(Q5) In ∆ABC, XY ∥ AC and XY divides the triangle into two parts of equal area. Find the ratio of
AX
XB

ABCXY

Solution :

Given :In ∆ABC, XY ∥ AC.

XY divides ∆ABC into two points of equal area.

In ∆ABC, ∆XBY

∠B = ∠

= ∠X

∠C = ∠

[∵ XY ∥ AC; (∠A, ∠X) and ∠C, ∠Y are the pairs of corresponding angles]

Thus ∆ABC ∼ ∆XBY by A.A.A similarity condition.

Hence
∆XBY
=
AB2

[∵ The ratio of areas of two similar triangles is equal to the ratio of squares of their corresponding sides]

=
AB2
XB2

[Given, ∆BXY = ∆BAC]

[∴ ∆ABC = 2. ∆XBY]

= (
AB
XB
)2
= (
+
XB
)2
= (
+
) ⇒ 2 = (
AX
XB
+ )2
AX
XB
+ 1 = √
AX
XB
=√ -
Hence the ratio
AX
XB
=
-