Question

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

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

Answer 1

The correct option is C ${30}^o$

$\angle EFD=?$

$\angle ABC=\angle DCE={60}^o$ (Corresponding angle )

$\therefore \angle FCE=180-60={120}^o$ (Property of traversal line)

But, $\angle FCE+\angle CEF+\angle CFE={180}^o$ (Property of triangle)

$\therefore \angle CFE=180-120-30=180-150={30}^o$.

But

$\angle CFE=\angle CFD$

$\angle CFD={30}^0$