SaiBook.us Geometry

Lesson

Title: Perimeter of Triangle(based on angles)

Grade: 4-a Lesson: S1-L8

Explanation: Hello students, let us learn a new topic in geometry today with definitions, concepts, examples, and worksheets included.

Lesson:

Definition: Acute Angle Triangle

A triangle is a three-sided polygon with three angles and three vertices.

A triangle in which all three angles are acute, meaning they are less than 90 degrees each.

The perimeter of an acute triangle, simply adds up the lengths of its three sides.

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Explanation: This image shows an acute-angle triangle.

Definition: Right Angle Triangle

A triangle that has one angle measuring exactly 90 degrees, known as a right angle.

The perimeter of an right triangle, simply adds up the lengths of its three sides.

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Explanation: This image shows an right angle triangle.

Definition: Obtuse Angle Triangle

A triangle in which one angle is obtuse, meaning it is greater than 90 degrees but less than 180 degrees.

The perimeter of an obtuse triangle, you simply add up the lengths of its three sides.

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Explanation: This image shows an obtuse angle triangle.