Question

Which characteristics best describe an obtuse isosceles triangle? I. One angle is greater than 90°. II. All side lengths are equal. III. Two sides meet at a 90° angle. IV. Two sides are equal in length. A. I and IV B. II and III C. I and II D. III and IV

Answer 1

An obtuse triangle is a triangle that has an angle greater than 90 degrees, so 1. One angle is greater than 90 degrees is correct.

Answer 2

An obtuse isosceles triangle is defined as a three-sides triangle shape that has one angle (out of three angles) more than 90 degrees and whose two sides are always congruent that includes obtuse angle in between. So it will follow :-

⇒ Obtuse means "one angle is greater than 90 degrees".

⇒ Isosceles means "Two sides are equal in length".

So, option A is correct, i.e. statements I and IV.