Respuesta :

Given:

The diagram shows two right-angled triangles OAB  and OCD.

To find:

The length of BD.

Solution:

Let the length of BD is x.

In triangle OAB and OCD,

[tex]\angle AOB\cong \angle COD[/tex]           (Common angle)

[tex]\angle ABO\cong \angle CDO[/tex]           (Right angle)

[tex]\Delta OAB\sim OCD[/tex]                           (By AA property of similarity)

We know that, the corresponding sides of similar triangles are proportional. So,

[tex]\dfrac{AB}{CD}=\dfrac{OB}{OD}[/tex]

[tex]\dfrac{4}{7}=\dfrac{14}{14+x}[/tex]

[tex]4(14+x)=14(7)[/tex]

[tex]56+4x=98[/tex]

Subtracting 56 from both sides, we get

[tex]4x=98-56[/tex]

[tex]4x=42[/tex]

[tex]x=\dfrac{42}{4}[/tex]

[tex]x=10.5[/tex]

Therefore, the length of BD is 10.5 cm.