Question

In the given figure, $AB\parallel CD$, then $\angle EFD$ is equal to:

• A. $20$ ${}^{\circ }$
• B. $25$ ${}^{\circ }$
• C. $30$ ${}^{\circ }$
• D. $35$ ${}^{\circ }$

Answer 1

The correct option is C $30$ ${}^{\circ }$

Since, $AB\parallel CD$, thus $\angle ABC=\angle DCE={60}^{\circ }$ ....(corresponding angles)
$\angle DCE+\angle FCE={180}^{\circ }$ ....(supplementary angles)
$\angle FCE={120}^{\circ }$
In triangle, $EFC$,
$\angle CEF+\angle FCE+\angle EFD={180}^{\circ }$
$\angle EFD=180-120-30$
$\angle EFD={30}^{\circ }$.