# Why are all equilateral triangles acute?

All the angles are ${60}^{o}$.
In a equilateral triangle, all the angles are equal. All the angles in a triangle sum up to ${180}^{o}$. We can determine the angles by dividing 180 by 3 (the three angles) to get 60. Therefore we can determine that each angle is ${60}^{o}$. All acute angles are below ${90}^{o}$.