LINES, ANGLES, AND TRIANGLES

LINES

LinesA line is a series or

connection of points. It has length but has no width or thickness.

It may be straight, curved or a combination of the two.

Lines

A straight line is unlimited in extent. It may be extended in either direction infinitely. It is generated by a point moving always in the same direction.

LinesA curved line is

generated by a point moving in a continuously changing direction.

LinesA ray is the

part of a straight line beginning at a given point and extending limitlessly in one direction.

LinesA line segment is a part

of a straight line between two of its points. The two points of line segment is called endpoints.

Lines

A line is named or designated by capital letters of any two points or by a small letter.

ANGLES

AnglesAn angle is a figure

formed by two rays with a common endpoint. The rays are the sides of an angle, while the end point is its vertex.

AnglesKinds of Angles:Acute angle – is an angle

that measures less than 90◦

Right angle – is an angle that measures exactly 90◦

AnglesObtuse angle – is an angle

whose measure is more than 90◦ and less than 180◦

Straight angle – is an angle that measures exactly 180◦

AnglesReflex angle – is an angle

whose measure is more than 180◦ and less than 360◦

AnglesExamples of Angles:

Angles

TRIANGLES

TrianglesA triangle is a

polygon having three sides.

TrianglesKinds of Triangles:(According to LENGTH of Sides)

Scalene triangle – is a triangle having no congruent sides

TrianglesIsosceles triangle – is a

triangle having at least two congruent sides

Equilateral triangle – is a triangle having three equal sides

TrianglesKinds of Triangles:(According to the its ANGLES)

Right triangle – is a triangle having a right angle

TrianglesObtuse triangle – is a

triangle having an obtuse angle

Acute triangle – is a triangle having three acute angles

TrianglesThe Pythagorean Theory:

a2 = b2 + c2

A theorem attributed to Pythagoras that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides.

End of Presentation …THANK YOU !!!

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