Find $ \mathrm{x} $ if $ \mathrm{AB}\|\mathrm{CD}\| \mathrm{EF} $.
"
Given:
$AB \parallel CD \parallel EF$.
To do:
We have to find the value of $x$.
Solution:
Let $\angle ECD=y$
$CD \parallel EF$ and $CE$ is the transversal.
This implies,
$\angle ECD$ and $\angle CEF$ are consecutive interior angles.
$\angle ECD+\angle CEF=180^o$
$y+140^o=180^o$
$y=180^o-140^o$
$y=40^o$
$AB \parallel CD$ and $BC$ is the transversal.
This implies,
$\angle BCD$ and $\angle ABC$ are alternate interior angles.
$\angle ABC=\angle BCD$
$60^o=x+y$
$60^o=x+40^o$
$x=60^o-40^o$
$x=20^o$
The value of $x$ is $20^o$.
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