Question

In triangle ABC, AC=15cm and DE||BC . lf AB/AC=3, find EC

Answer 1

Given:

In triangle ΔABC, AC= 15 cm and DE||BC . $\mathbf{If\ \frac{AB}{AD}=3}$

To Find:

Find value of EC.

Solution:

Here it is given that DE║BC ,so we can write:

$\mathbf{\dfrac{AD}{AB}=\dfrac{AE}{AC}}$

Or

$\mathbf{\dfrac{AE}{AC}=\dfrac{AD}{AB}}$

On putting respective value in above equation:

$\mathbf{\dfrac{AE}{15}=\dfrac{1}{3}}$

$\mathbf{AE=15\times \dfrac{1}{3}}$

So:

AE = 5 cm

AC can be also written as:

AE + EC = AC

5 + EC = 15

EC = 15 - 5

EC = 10 cm

Means value of EC is 10 cm.

Answer 2

Answer:

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