Question

which names describe this triangle? choose yes or no for each name.
acute
right
obtuse
equilateral
isosceles
scalene

Explanation:

Step1: Check angle type

An obtuse triangle has one angle greater than \(90^{\circ}\). From the shape, it has an obtuse angle. So, obtuse - Yes. Acute (all angles \(< 90^{\circ}\)) - No. Right (one angle \(= 90^{\circ}\)) - No.

Step2: Check side - related types

An isosceles triangle has at least two equal sides. Visually (from the symmetrical appearance), it has two equal sides. So, isosceles - Yes. Equilateral (all three sides equal) - No. Scalene (all three sides different) - No.

Answer:

• acute: No
• right: No
• obtuse: Yes
• equilateral: No
• isosceles: Yes
• scalene: No