Question

The sum of the acute angles of an obtuse triangle is ${70}^o$ and their difference is ${10}^o$. The largest angle is:

• A. ${110}^o$
• B. ${105}^o$
• C. ${100}^o$
• D. ${95}^o$

Answer 1

The correct option is A ${110}^o$

Since, in an obtuse triangle one angle is obtuse angle.

$\therefore$ Other two angles of an obtuse triangle are acute.

Sum of two acute angles$={70}^o$

$\therefore$ Obtuse angle$={180}^o-{70}^o={110}^o$

Option $A$ is correct.