Polygons… SOL5.13 GES Mrs. Norman

Which Shapes Are Polygons? Why? Not Polygons

What is a Polygon? A polygon is a closed plane figure made up of line segments. The names of common polygons tell how many sides the polygon has. vertex 2 3 3 2 2 side 3 2 2 4 4 3 3 3 3 2 2 4 3 2 Triangle (3 sides) Quadrilateral (4 sides) Pentagon (5 sides) Hexagon (6 sides) Octagon (8 sides)

What is a Regular Polygon? Clue: What do these polygons have in common? A regular polygon has sides of equal length and angles of equal measure These are regular polygons 5 2 3 3 2 2 4 4 5 2 2 5 3 3 2 2 4 5 3 2 Triangle (3 sides) Quadrilateral (4 sides) Pentagon (5 sides) Hexagon (6 sides) Octagon (8 sides)

Polygon Videos BrainPop

Classifying Angles (Review)

Acute Angle An acute angle has a measure between 0° and 90°. (a cute = little)

Right Angle A right angle has a measure of 90°. (square = right = 90°)

Obtuse Angle An obtuse angle has a measure between 90° and 180°. (obtuse = obese)

Straight Angle A straight angle has a measure of 180°. (straight = flat)

Classifying Triangles (Review)

Classifying Triangles Equilateral triangle All sides are the same (equal) length. The sum total of every triangle = 180° So, if all of the angles are the same… 3 ÷ 180° = 60° Each of the three angles of an equilateral triangle is 60°

Classifying Triangles Isosceles triangle At least two sides are the same (equal) length. 4 4 6 4 4

Classifying Triangles Scalene triangle No sides are the same (equal) length. 9 2 7 9 2 7

Classifying Triangles Right triangle One angle is a right (90°) angle. The sides have special names. The legs are the two sides that form a right triangle The third side is the hypotenuse hypotenuse hypotenuse legs legs

Classifying Triangles Acute triangle All three angles are acute angles.

Classifying Triangles Obtuse triangle One angle is an obtuse angle.

Classifying Quadrilaterals

Classifying Quadrilaterals How do you classify quadrilaterals? Quadrilaterals can be classified by their angles pairs of sides. Remember that a quadrilateral is any polygon with 4 sides.

Classifying Quadrilaterals Types of quadrilaterals? Parallelogram Rectangle Rhombus Square Trapezoid

Classifying Quadrilaterals Parallelogram A quadrilateral with both pairs of opposite sides parallel equal in length. Parallelogram Rectangle Rhombus Square

Classifying Quadrilaterals Rectangle A parallelogram with four right (90°) angles. Rectangles & rhombuses are special parallelograms. Rectangle Square

Classifying Quadrilaterals Rhombus A parallelogram with all sides the same length. Rectangles & rhombuses are special parallelograms. Rhombus Square

Classifying Quadrilaterals Square A rectangle with all sides the same length. A square is a special rectangle. It is also a special rhombus. Square

Classifying Quadrilaterals Trapezoid A quadrilateral with only one pair of parallel sides. A Trapezoid side A ll side C side B ll side D D B C

ixl Classify Quadrilaterals Quadrilateral Videos ixl Classify Quadrilaterals

You now know all about Plane Figures!