An acute angle is an angle with a measure less than 90°.
A right angle is an angle with a measure of 90°.
An obtuse angle is an angle with a measure greater than 90°.
acute angle | right angle | obtuse angle |
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less than 90° | 90° | greater than 90° |
An acute triangle is a triangle with 3 acute angles.
A right triangle is a triangle with 1 right angle.
An obtuse triangle is a triangle with 1 obtuse angle.
acute triangle | right triangle | obtuse triangle
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3 acute angles | 1 right angle | 1 obtuse angle |