Question

There are three triangles A, B and C with the following angles. Which among these is an obtuse triangle?

Triangle A: with angles ${45}^{\circ }$, ${55}^{\circ }$ and ${80}^{\circ }$

Triangle B: with angles ${60}^{\circ }$, ${55}^{\circ }$ and ${65}^{\circ }$

Triangle C: with angles ${32}^{\circ }$, ${107}^{\circ }$ and ${41}^{\circ }$.

• A. Triangle A
• B. Triangle B
• C. Triangle C
• D. (a) and (b) above.

Answer 1

The correct option is C Triangle C

In an obtuse type of triangle, one angle must be more than $90$ degree.
Only in triangle C, we have one angle larger than $90$ degree, so triangle C is an obtuse triangle.