Question

Question 9
The number of obtuse angles in the given figure is
a) 2
b) 3
c) 4
d) 5

Answer 1

An obtuse angle is an angle whose measure is more than ${90}^{\circ }$ but less than ${180}^{\circ }$.

There are 4 obtuse angles

$\angle BOC$ + $\angle DOC$ = ${30}^{\circ }$ + ${65}^{\circ }$ = ${95}^{\circ }$

$\angle EOD$ + $\angle DOC$ +$\angle COB$ = ${45}^{\circ }$ + ${65}^{\circ }$ + ${30}^{\circ }$ = ${140}^{\circ }$

$\angle EOD$ + $\angle DOC$ = ${45}^{\circ }$ + ${65}^{\circ }$ = ${110}^{\circ }$

$\angle AOE$ + $\angle EOD$ +$\angle DOC$ = ${65}^{\circ }$ + ${45}^{\circ }$ + ${40}^{\circ }$ = ${150}^{\circ }$