Question

Given that $AB\parallel DE,\angle ABC={115}^{\circ };\angle CDE={140}^{\circ }$. What is $\angle BCD$?

• A. ${45}^{\circ }$
• B. ${55}^{\circ }$
• C. ${65}^{\circ }$
• D. ${75}^{\circ }$

Answer 1

The correct option is D ${75}^{\circ }$

Produce $AB$ and $ED$
$\angle CBF={65}^{\circ }$ and $\angle LDF={40}^{\circ }=\angle BFC$
$\angle BCD={180}^{\circ }-({65}^{\circ }+{40}^{\circ })={75}^{\circ }$