Post on 07-Oct-2020
Chapter 8: Area8.1/8.2 Area of Basic Figures
Objectives: Understand and solve the areas of parallelograms, triangles, trapezoids, and rhombi.
**What about rectangles?
**What about squares?
Find the area or missing side:
Area of a triangle:
Find the area:
10
Chapter 8: Area
Find the unknown measurement of the triangle if the area is 30 ft2 and the base is 10 ft.
Area of a Trapezoid:
Find the area:
Area of a Rhombus:
Chapter 8: Area
Find the area:
8.3 The Pythagorean Theorem
Chapter 8: Area
Find the missing length in the right triangle:Legs of 8 and 15. Legs of 10 and 24. Legs of 5 and 12.
Hypotenuse 25, leg 20. Hypotenuse 7, leg 5. Hypotenuse 61, leg 60.
Given the 3 side lengths, are the following triangles right triangles?15, 36, and 39 10, 20, and 22 14, 48, and 50
8.4 Regular Polygons
Chapter 8: AreaVocabulary:Regular polygon:
Center of a regular polygon:
Radius of a regular polygon:
Apothem of a regular polygon:
Central angle of a regular polygon:
Base angle of a regular polygon:
Objectives:Define terms related to regular polygons.Derive and apply a formula for the area of regular polygons.
The central angles of a regular n-gon are congruent and measure 360°n .
What are the measures of the central angles and the base angles of a regular hexagon?
The area of a regular polygon is one-half the product of its apothem and its perimeter: A=1
2ap
The apothem of an equilateral triangle is one-third the length of the altitude: a=13 h
Find the areas:
8.5 Area of Circles
Chapter 8: Area
Find the area:
Composite figures - find the area of the shaded region
8.6 Surface Areas of Prisms and CylindersVocabulary:Surface area:
Objectives:Differentiate between surface area and lateral surface area.
Chapter 8: AreaDerive and apply formulas for calculating the surface area of prisms and cylinders.
Nets:
To calculate surface area of a prism/cylinder:Find Lateral Surface Area. Add the 2 bases to it.
Find the surface areas:
Chapter 8: Area
8.7 Surface Areas of Pyramids and ConesObjectives:Distinguish between the total surface area and the lateral surface area of pyramids and cones.Derive and apply formulas for calculating the surface area of pyramids and cones.
Pyramids: Add up the areas of the triangles and the area of the base.S=L+B L=lateral surface area, B=area of base
Find the surface area:
Chapter 8: Area
Cones: Add up the slanted side of the cone and the area of the circular base. S=πrl+π r2 r=radius, l=slant height
Find the surface area:
8.8 Surface Areas of Polyhedra and SpheresObjectives:State and apply the formula for surface area of a sphere.Name the regular polyhedra.State and apply formulas for surface areas of regular polyhedral.
Spheres: S=4 π r2
Find the surface area:
Chapter 8: Area
Regular Polyhedron: a polyhedron with faces bounded by congruent regular polygons and with the same number of faces intersecting at each vertex.
To find the surface area:S=nA n=number of faces, A=area of one face
Area of one face=5