Presentation on theme: "Intro to Geometry in 2D These are your notes for Area of 2 Dimensional figures…Write & Draw EVERY detail as if I was at the front of class. Write down."— Presentation transcript:
1 Intro to Geometry in 2DThese are your notes for Area of 2 Dimensional figures…Write & Draw EVERY detail as if I was at the front of class. Write down any questions you may have, ask the substitute, or a neighbor!
2 HAVE YOU NOT GOT OFF THIS SLIDE YET? COME ON! GET MOVING GUYS!By:Jeffrey McAven
3 Lets look at 2 Dimensional Shapes and their Formulas Triangles (3 sides)Quadrilaterals (4 sides)Polygons-3 or more sides, must be closed, no curved or overlapping sides
4 Polygons- Any closed shape made up of straight lines. We have already talked about Triangles and Quadrilaterals, lets look at some more common polygons.Pentagon (5 sides)Hexagon (6 sides)Heptagon (7 sides)Octagon (8 sides)Nonagon (9 sides)Decagon (10 sides)You do not need to know the formulas for these but should be able to recognize them.
5 PerimeterTo find the perimeter of any polygon all you need to do is add the sides.
7 QuadrilateralsA Quadrilateral is any four sided figure. Lets look at the most common.Square – All Sides and Angles same A=s2 or A=base(height)Rectangle – All Angles are the same and parallel sides are the same measure A=base(height)
8 Squares and Rectangles Area of Rectangle: A = bhArea of Square: A = s²sA = s²bhA = bhExample:Example:1256A = 6² = 36 sq. unitsA = 12 x 5 = 60 sq. units
9 Quadrilaterals Parallelogram – Parallel side are the same A=bh Rhombus A=bhTrapezoid
10 Parallelograms & Rhombus Area of Parallelogram: A = b(h)Area of Rhombus: A = b(h)Example:hbExample:69A = 9 x 6 = 54 sq. units
11 TrapezoidsOrThe height (h) is the distance between the two bases b1 & b2, perpendicular to each basehb1b2
12 TrianglesA Triangle is a three sided figure. All triangles have the same Area formula or
13 Triangles Right Triangle – Has one angle 90○ Acute Triangle – Every angle is less than 90○Obtuse Triangle –Has one angle more than 90○
14 TrianglesEquilateral Triangle – All angles and sides are the same measureIsosceles Triangle – Two sides are the same and two angles are the sameScalene Triangle – All sides and angles are different
15 TrianglesOrh is the distance from a vertex of the triangle perpendicular to the opposite side.hb
16 CirclesCircumference of a circle is the distance around the outside of the circle. The formula is C=2πr or C= πdArea formula for a circle is A= πr2
17 Area of a CircleArea formula for a circle is A= πr2
18 Circumference of a Circle Circumference formula for a circle isor
19 Area of Composite Figures The area of a composite figure is the sum of all of its non-overlapping parts.81012414A = ½(8)(10)A= 40A = (12)(10)A= 120A = (4)(8)A=32A = (14)(8)A=112Area = = 304 sq. units