A triangle is a plane figure with three sides.
Examples:
A triangle is a three-sided polygon.
Examples:
There are three angles inside every triangle. The sum of a triangle's interior angles is always 180 degrees (°).
There are different kinds of triangles. Triangles are classified according to the characteristics of their sides and their angles.
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An equilateral triangle has three congruent sides (of equal measurement). |
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It also has three congruent 60-degree (°) angles. |
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Characteristics |
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A scalene triangle has three sides with different measurements. |
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It also has three angles with different measurements. |
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Characteristic |
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A right triangle always contains a right angle (90°). |
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A right triangle can also be isosceles or scalene.
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Isosceles right triangle |
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It has the main characteristic of a right triangle (a right angle). |
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It also has the characteristics of an isosceles triangle (two congruent sides and two congruent angles). |
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Scalene right triangle |
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It has the main characteristic of a right triangle (a right angle). |
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It also has the characteristics of a scalene triangle (three sides and three angles of different measurements). |
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