Robert says that he can draw an obtuse equilateral triangle. Jonas says that is not possible. Who is correct and why?

A.

Robert is correct as long as the other two angles are acute and all of the sides are the same length.

B.

Jonas is correct because an equilateral triangle has 3 acute angles and all sides the same length.

C.

Robert is correct because all equilateral triangles have 1 obtuse angle and all sides the same length.

D.

Jonas is correct because equilateral triangles have one right angle and two sides the same length.

An Equilateral Triangle is such a triangle in which all the angles and sides are equal in measure.

The sum of 3 angles in a triangle must be equal to 180 degrees and the measure of an obtuse angle is greater than 90 degrees. If we set an angle of the triangle greater than 90 degrees (i. e. obtuse), it will never be possible to set the remaining angles to the same measure. The rest two angles will be less than 90 degrees. This way all three angles can never be the same and, therefore, obtuse equilateral triangle is not possible.

So, the correct answer is option B