Question

classifying triangles classify the triangle by its angles and by its sides.

1. t u 42° 42° v

Explanation:

Step1: Classify by angles

Since two angles (\(42^{\circ}\) each) are equal, find the third angle. Using the angle - sum property of a triangle (\(\angle T+\angle U+\angle V = 180^{\circ}\)), \(\angle V=180-(42 + 42)=96^{\circ}\). A triangle with one angle greater than \(90^{\circ}\) is an obtuse triangle.

Step2: Classify by sides

Since two sides (marked with the same cross - hatch) are equal, it is an isosceles triangle.

Answer:

By angles: obtuse triangle. By sides: isosceles triangle.