Question

In a $\Delta ABC$, if $\angle B$ is an obtuse angle, then the longest side is:

• A. $AB$
• B. $BC$
• C. $AC$
• D. none

Answer 1

The correct option is C $AC$

Side opposite to the largest angle is the longest side.

It is given that, $\angle B$ is obtuse , so the other two angles must be acute angles.

So, $\angle B$ is the largest angle and the side opposite to it is $AC$

Hence, $AC$ is the longest side.