Classifying Triangles by Angles and Length

An acute triangle is a triangle in which ______ angles are acute angles (less than 90 degrees)

• 1

• 2

• 3

An obtuse triangle has at least one angle that is bigger than ______ degrees.

• 90

• 45

• 180

Triangles can be classified by what two things?

• Side length

• Number of Vertices

• Angles

• Congruent Sides

What type of triangle has only acute angles and no congruent sides?

• Right Isosceles Triangle

• Obtuse Isosceles Triangle

• Right Scalene Triangle

• Acute Scalene Triangle

A triangle with sides of length 6 cm, 11 cm, and 14 cm is ​ ​ (a)   .

• an acute triangle

• not a triangle

• a right triangle

• an obtuse triangle

Wendy cut a rectangular piece of glass in half for her stained glass window design. The tile was a square. She made one cut along a diagonal from one vertex to another vertex. Classify the two triangles resulting from the cut by their angles and their side lengths.

Easton says he has a triangle with 1 obtuse angle and 3 different side lengths. Select the statement that correctly identifies this triangle.

• The triangle must be an obtuse scalene triangle

• This triangle must be an obtuse isosceles triangle

• The triangle must be an obtuse right triangle

• The triangle must be an obtuse equilateral triangle

Match the following:

• 1,2,3

• Obtuse Triangle

• 9,12,15

• Acute Triangle

• 7,7,9

• No Triangle

• 8,12,17

• Right Triangle

What type of triangle has only one right angle and two congruent sides?

• Right Isosceles Triangle

• Obtuse Isosceles Triangle

• Right Scalene Triangle

• Acute Scalene Triangle

A triangle with at least one angle greater than 90 degrees is called a(n) ________ triangle

• obtuse

• left

• right

• acute