In the following figure, point D divides AB in the ratio 3: 5. If BC = 4.8 cm, find the length of DE. - Noon Academy

In the following figure, point D divides AB in the ratio 3: 5. If BC = 4.8 cm, find the length of DE.

Class 10 | Exercise 15B | ICSE | Maths | Selina | Similarity (With Applications to Maps and Models)

In the following figure, point D divides AB in the ratio 3: 5. If BC = 4.8 cm, find the length of DE.

Selina Solutions Concise Class 10 Maths Chapter 15 ex. 15(B) - 1

Solution:

Because,

$\vartriangle ADE\text{ }\sim\text{ }\vartriangle ABC\text{ }by\text{ }AA$

criterion for similarity

So, we have

$AD/AB\text{ }=\text{ }DE/BC$

$3/8\text{ }=\text{ }DE/4.8$

So,

$DE\text{ }=\text{ }1.8\text{ }cm$

i

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