Question

Given that , $\angle ABD={30}^o,\angle EBF={40}^o,\angle FBC={30}^o$, then find $\angle DBE$.

• A. ${70}^o$
• B. ${110}^o$
• C. ${100}^o$
• D. ${80}^o$

Answer 1

Answer: (D)

${80}^o$

We know that,
$\angle ABD+\angle EBF+\angle FBC+\angle DBE={180}^o$ (Angles on same side of straight line)
$\Rightarrow {30}^o+{40}^o+{30}^o+\angle DBE={180}^o$
$\Rightarrow {100}^o+\angle DBE={180}^o$
$\Rightarrow \angle DBE={180}^o-{100}^o$
$={80}^o$