Polygons

Square – Rectangle – Triangle – Rhombus – Parallelogram -

Trapezium

Square

-Four sides -Four angles

-Four vertices -The diagonals are equal in

length and perpendicular and bisect each other.

Rectangle

-Four sides -Four angles

-Four vertices -The diagonals are equal in length

and not perpendicular and bisect each other .

Triangle

-Three sides -Three angles

-Three vertices -The sum of measures of the interior

angles of any triangle = 180⁰

Type of triangle according to the length of its sides .

-Isosceles triangle -Equilateral triangle

-Scalene triangle

Type of triangle according to the measures of its angle .

-Acute angle -Obtuse angle

-Right angle

Notice

For any polygon

number of sides = number of vertices = number of angles

Exercise put ( √ ) for the correct answer

and put ( × ) for the incorrect answer .

(1 ) there can be two right angle in one triangle ) (

(2 ) there can be three acute angles in one triangle ) (

(3 ) in the rectangle every two opposite sides are equal in length ) (

(4 ) the diagonals of the square are not perpendicular ) (

Modified by

Sara Mahmud