Transcript Limits and Their Properties - Dang's Math Class

PAGE 603 AND 767
14)
576 cm2
15)
13.2548 ft2
16)
1582.5469 in2
17)
14.5309 ft2
27)
84.2755 cm2
29)
46.7653 m2
31)
90.8482 ft2
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12)
13)
14)
26)
𝟓𝟎𝟎
 𝒎𝟐
3
𝟒𝟓
 𝒊𝒏𝟐
2
𝟒𝟕
π 𝒇𝒕𝟐
90
𝟔
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COMPOSITE FIGURES
Section 9–3
Geometry PreAP, Revised ©2014
[email protected]
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DEFINITIONS
A. Composite figures are made up of two or more geometric shapes.
B. Perimeter
1.
2.
Determine all lengths and widths
Combine like terms
C. Area
1.
2.
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Determine all lengths and widths
Break up all of the shapes
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FORMULAS
A. Perimeter
1.
2.
Circumference: 2πr
Perimeter: Add all of the sides up
B. Area
1.
Parallelogram: A = bh
2.
Triangle: 𝑨 =
3.
Trapezoid: 𝑨 =
𝒃𝒉
𝟐
𝒉
4.
Circle: 𝑨 = 𝝅𝒓𝟐
𝒃𝟏 +𝒃𝟐
𝟐
5.
Regular Polygon: 𝑨 =
𝒂𝑷
𝟐
6.
Rhombus/Square/Kite: 𝑨 =
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𝒅𝟏 𝒅𝟐
𝟐
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EXAMPLE 1
Find the shaded area. Show all formulas and leave answer in π.
1
Area of  Circle  Rectangle+Triangle
2
1
bh
2
A   r   lw 
2
2
12 14 

1
2
A   10    20 14  
2
2
A  50 +364mm
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6
EXAMPLE 2
Find the shaded area. Show all formulas.
A = bh = 8(5)= 40ft2
A  65 ft
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7
YOUR TURN
Find the shaded area. Show all formulas.
A  1781.25 m
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EXAMPLE 3
Find the shaded area. Show all formulas and leave answer in π.
Area  Circle  Trapezoid
 b1  b2 
A   r   
h
 2

2
 12    20 

A   100   
8 
2


A  100  128 cm
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YOUR TURN
Find the shaded area. Show all formulas and leave answer in π.
A  9  18 in
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EXAMPLE 4
A pool is being built just in time for summer. Determine the
area needed to build this pool.
Area  Rectangle  Trapezoid
 b1  b2 
A   l  w   
h
 2

  4    6

A   2814   
2 
2


A  402 ft
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EXAMPLE 5
Find the area of the dirt bike track in terms of pi and in terms of 4 decimal places.
Then, determine the cost to cover the entire track to with dirt, to the nearest cent
if each square foot costs $4.99 (excluding taxes).
Area  Bigger Circle  Smaller Circle
A    40     25
A   1600     625
2
2
A  975 ft ;3063.0528 ft
2
2
 $15, 284.63
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YOUR TURN
This side of the storage barn needs to be painted. Each gallon of paint
costs $20 and covers 350 square feet. Find the cost to paint this side.
Justify your answer with the proper work .
2 gallons
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ASSIGNMENT
Page 609: 9-13, 16-20 all
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