Question

1. △cde:
2. △bce:
3. △abe:
4. △bde:
5. △cfe:

3 congruent sides
classify each triangle in the diagram below by its angles.
2 congruent sides
no congruent sides
classify each triangle in the diagram below by its sides.

1. △jkm:
2. △kln:
3. △jkn:

classify each triangle by its angles and sides.
9.
10.
11.

Explanation:

Step1: Recall triangle - angle classification

A right - triangle has one 90° angle, an obtuse - triangle has one angle greater than 90°, and an acute - triangle has all angles less than 90°. An equiangular triangle has all angles equal (each 60°).

Step2: Recall triangle - side classification

An equilateral triangle has 3 congruent sides, an isosceles triangle has 2 congruent sides, and a scalene triangle has no congruent sides.

Step3: Classify triangle 9

It has a 90° angle (right - angle) and 2 congruent sides. So it is a right - isosceles triangle.

Step4: Classify triangle 10

It has an angle of 114° (greater than 90°) and no congruent sides. So it is an obtuse - scalene triangle.

Step5: Classify triangle 11

It has all angles 60° (equiangular) and 3 congruent sides. So it is an equilateral (also equiangular) triangle.

Answer:

1. Right - isosceles triangle
2. Obtuse - scalene triangle
3. Equilateral (equiangular) triangle