Classifying Triangles by Angles

Classify this triangle.

• Acute

• Obtuse

• Right

Classify this triangle.

• Right

• Acute

• Obtuse

Select the obtuse triangle.

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Select the acute triangle.

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When classified by its angles this is a/an _____ triangle.

• right

• obtuse

• acute

When classified by its angles this is a/an _____ triangle.

• obtuse

• right

• acute

When classified by its angles this is an acute triangle because _____.

• it has one acute angle

• it has two acute angles

• all three angles are acute

When classified by its angles this is an obtuse triangle because _____.

• it has one angle less than 90°

• it has one angle equal to 90°

• it has one angle more than 90°

Select all of the acute triangles.

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Select all of the right triangles.

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