Types of Triangles

Types of Triangles

Classify a Triangle by its sides and angles

Equilateral Triangle

• All 3 sides are equal in length.

• All 3 angles measure the same.

Scalene Triangle

• All 3 sides have different lengths.

• All 3 angles have different measurements.

Scalene Acute Triangle

• All 3 sides have different lengths.

• All 3 angles have different measurements.

• All 3 angles are less than 90^o.

Scalene Right Triangle

• All 3 sides have different lengths.

• All 3 angles have different measurements.

• One angle is 90^o.

Scalene Obtuse Triangle

• All 3 sides have different lengths.

• All 3 angles have different measurements.

• One angle is greater than 90^o.

Multiple Choice

Classify the triangle.

• Equilateral

• Scalene Acute

• Scalene Right

• Scalene Obtuse

Multiple Choice

Classify the triangle.

• Equilateral

• Scalene Acute

• Scalene Right

• Scalene Obtuse

Multiple Choice

Classify the triangle.

• Equilateral

• Scalene Acute

• Scalene Right

• Scalene Obtuse

Isosceles Triangle

• Two sides are of equal length.

• The angles opposite to the equal sides are also equal.

Isosceles Acute Triangle

• Two sides are equal.

• Two angles are equal.

• All angles are less than 90^o.

Isosceles Right Triangle

• Two sides are equal.

• Two angles are equal.

• One angle is 90^o.

Isosceles Obtuse Triangle

• Two sides are equal.

• Two angles are equal.

• One angle is greater than 90^o.

Multiple Choice

Classify the triangle.

• Equilateral

• Isosceles Acute

• Isosceles Right

• Isosceles Obtuse

Multiple Choice

Classify the triangle.

• Equilateral

• Isosceles Acute

• Isosceles Right

• Isosceles Obtuse

Fill in the Blank

What is the measurement of the 3rd side of this isosceles triangle?

Fill in the Blank

What is the measurement of angle x for this isosceles triangle?

Fill in the Blank

What is the measurement of AC if AB = 11?

Fill in the Blank

What is the measurement of ED if EF = 16?

Multiple Choice

Triangle ABC is what type of triangle?

• Equilateral

• Scalene

• Isosceles

• Right Triangle

Match

Match the following triangles with their side and angle classification.

Equilateral

Scalene Obtuse

Scalene Right

Isosceles Acute

• Equilateral

• Scalene Obtuse

• Scalene Right

• Isosceles Acute