triangles, quadrilaterals and polygons

• the sum of interior angles for triangles


  180
• An equilateral triangle has all its sides equal length and all its angles are equal to 60 degrees.
• what is an isoceles triangle?


  Triangle with two equal sides.
• what is a scalene triangle?


  A triangle with three unequal sides.
• the largest side is opposite the largest angle and the smallest side is opposite the smallest angle
• the sum of the length of any two sides is greater than the length of the 3rd side
• what are quadrilaterals?


  4 sided figures
• the interior angles of a quadrilateral add up to 360
• there are two diagonal lines in a quadrilateral
• quadrilaterals include parallelograms, rhombus, rectangles, squares, trapeziums and kites
• parallelograms have 2 pairs of parallel sides and 2 pairs of corresponding angles
• perpendicular lines are lines that intersect at 90 degrees
• regular polygons can be constructed by drawing equilateral triangles on top of each other
• a regular polygon has all its sides equal length and all its internal angles equal measure
• exterior angles add up to 360 degrees for all polygons
• when a diagonal line bisects another diagonal line the sides will be equal
• a polygon is a closed plane figure with at least 3 sides
• what are the eight types of polygons?


  Triangle, Quadrilateral, Pentagon, Hexagon, Heptagon, Octagon, Nonagon, Decagon
• the equation for the sum of interior angles


  (number of sides - 2) x 180
• what is symmetry?


  Symmetry is a balanced arrangement of parts or elements that are identical or similar.
• what is rotational symmetry?


  no. of times the shape matches itself when you rotate it including the time where it returns to its original position