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Plane Figures. SOL5.13 GES Mrs. Norman. Which Shapes Are Polygons? Why?. Polygons. 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. 2. 2. 3. 3. side.
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Plane Figures SOL5.13 GES Mrs. Norman
Which Shapes Are Polygons? Why? Polygons 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 2 2 3 3 side 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)
Plane Geometric Figures A polygon is a closed plane figure with straight sides. A regular polygon has congruent sides. congruent the same size and shape
Quadrilaterals Trapezoid Exactly 1 pair of parallel sides Parallelogram 2 pairs of parallel sides Rhombus All sides congruent Square Kite 2 pairs of adjacent congruent sides 1 pair of congruent angles Rectangle Right angles
Quadrilaterals Trapezoid Exactly 1 pair of parallel sides Parallelogram 2 pairs of parallel sides Rhombus All sides congruent Square Kite 2 pairs of adjacent congruent sides 1 pair of congruent angles Rectangle Right angles
Describe and Compare Polygons: Sort polygons by their properties at http://illuminations.nctm.org/ActivityDetail.aspx?ID=34
Go to this site to make shapes with a virtual geoboard! http://matti.usu.edu/nlvm/nav/frames_asid_129_g_3_t_3.html If you annotate over the desktop with ActiveInspire you can measure their sides and angles!
Adding Angles of Polygons http://illuminations.nctm.org/ActivityDetail.aspx?ID=9 180 The angles of a triangle add to…. The angles of a quadrilateral add to…. Now explore further with this NCTM game: 360
What is a Regular Polygon? • Clue: What do these polygons have in common? • A regular polygon has sides of equal length and angles of equalmeasure These are regular polygons 5 2 3 3 2 2 4 5 2 2 4 5 3 3 2 2 4 5 3 2 Octagon (8 sides) Triangle (3 sides) Quadrilateral (4 sides) Pentagon (5 sides) Hexagon (6 sides)
Polygon Videos BrainPop
An acute angle has a measure between 0° and 90°. (a cute = little) Acute Angle
A right angle has a measure of 90°. (square = right = 90°) Right Angle
An obtuse angle has a measure between 90° and 180°. (obtuse = obese) Obtuse Angle
A straight angle has a measure of 180°. (straight = flat) Straight Angle
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 • 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 Rhombus Square Trapezoid Rectangle
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
Quadrilateral Videos ixl Classify Quadrilaterals