A polygon is a close up door geometric figure whose political parties are straightforward line segments. Each edge of a polygon where 2 sides intersect is referred to as a vertex that the polygon.

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For example, a triangle is a polygon with 3 sides. There are likewise three vertices, one at every point. This is the easiest polygon, since you can"t construct one with just 1 or 2 political parties (try it!).

Classification that Polygons

A polygon may be determined by the number of sides.

(1) A polygon with 4 sides is referred to as a quadrilateral.


(2) A polygon that 5 sides is referred to as a pentagon.


A polygon that 8 political parties is referred to as an octagon.


A polygon that 10 political parties is called a decagon.


A polygon of 12 political parties is referred to as a dodecagon.


NOTE: There room many an ext polygons, yet the ones noted here are several of the most popular and most often taught in geometry classes. Polygon with an ext than 12 sides are usually described as n-gons. Together in, a polygon v 56 sides is a 56-gon.

Other terms

In an equiangular polygon, each angle has actually the same degree measure. A square is an instance of an equiangular polygon since each that the 4 angles kind 90 degrees. The same can be said about a rectangle.


In an equilateral polygon, each side has the same length. In triangle abc below, every sides room 12 feet making triangle abc equilateral.


A regular polygon is BOTH equiangular and also equilateral. A square is a regular polygon due to the fact that all sides have the very same length and all angle measure the same: 90 degrees.

Classification of Triangles

Triangles might be share by

(A) your sides, or

(B) their angles

A scalene triangle has 3 various length sides.


an isosceles triangle has two same sides and also one side that is not equal.


An it is provided triangle has 3 equal sides.

In an acute triangle, every one of the angles will measure much less than 90 degrees.

A ideal triangle will always have one 90-degree angle.


one obtuse triangle will always have one angle whose measure up is higher than 90 degrees yet at the same time much less than 180 degrees.


Median and also Altitude (Height)

A typical of a triangle is a segment drawn from a vertex of the triangle to the midpoint of the opposite side.

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an altitude or elevation of a triangle is a segment attracted from a crest of the triangle perpendicular come the opposite next or to the opposite side extended.



The word street in geometry is always understood together the shortest path. The distance between a suggest and a line is the size of the perpendicular segment drawn from a suggest that is not on the heat to a allude on the line. The distance from A to heat BC below is 6, due to the fact that that is the size of the altitude