Transcript Quadrilaterals II - Pi Beta Phi Elementary
Quadrilaterals II
by Monica Yuskaitis
Quadrilateral Family
trapezoid parallelogram rectangle rhombus square Copyright © 2000 by Monica Yuskaitis
Definition
• Perimeter – (P) The distance around a figure.
5 9 in.
9 5 in.
5 in.
5 + 9 28 in.
9 in.
Copyright © 2000 by Monica Yuskaitis
Find the perimeter
9 cm.
9 cm.
9 9 cm.
9 9 + 9 9 cm.
36 cm.
A shortcut for the square is 4 x side.
Copyright © 2000 by Monica Yuskaitis
9 cm.
Find the perimeter
7 cm.
7 cm.
9 cm.
9 7 9 + 7 36 cm.
Copyright © 2000 by Monica Yuskaitis
10 ft.
Find the perimeter
10 ft.
6 ft.
10 ft.
+ 10 6 10 10 36 ft.
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12 m.
Find the perimeter
18 m.
11 m.
15 m.
+ 12 11 15 18 56 m.
Copyright © 2000 by Monica Yuskaitis
Definition
• Area – (A) the measure, in square units, of the surface of a figure.
The area of this rectangle is 8 squares.
Copyright © 2000 by Monica Yuskaitis
How to find the area of a square or rectangle.
Step 1 – Multiply the length times the width. (A = l x w) 3 cm.
x 5 3 15
5 cm.
Copyright © 2000 by Monica Yuskaitis
How to find the area of a square or rectangle.
Step 2 – Indicate that the answer is in square centimeters by writing the exponent 2 after the unit of measure.
3 cm.
5 cm.
Copyright © 2000 by Monica Yuskaitis
x 5 3 15 cm.
2
How to find the area of a square or rectangle.
Step 3 – Read the answer:
15 square centimeters.
3 cm.
5 cm.
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x 5 3 15 cm.
2
5 ft.
What is the area?
x 5 6 30 ft.
2 6 ft.
You say:
30 square feet.
Copyright © 2000 by Monica Yuskaitis
2 in.
What is the area?
6 in.
x 2 6 12 in.
2 You say:
12 square inches.
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4 m.
What is the area?
x 7 4 28 m.
2 7 m.
You say:
28 square meters.
Copyright © 2000 by Monica Yuskaitis
How to find the area of a parallelogram
Step 1 – Multiply the base times the height. (A = b x h) height 90º base Copyright © 2000 by Monica Yuskaitis
How to find the area of a parallelogram
Step 1 – Multiply the base times the height. (A = b x h) 2 height 13 in.
base 90º 17 in.
+
x
1
13 17
9 3 1
221
Copyright © 2000 by Monica Yuskaitis
How to find the area of a parallelogram
Step 2 – Indicate that the answer is in square inches by writing the exponent 2 after the unit of measure.
height x 13 17 13 in.
90º + 1 9 3 1
221 in.
2 base 17 in.
Copyright © 2000 by Monica Yuskaitis
How to check the area of a parallelogram height 2 cm.
90º base 4 cm, 4 x 2 = 8 cm.
2 First find the area.
Copyright © 2000 by Monica Yuskaitis
height 2 cm.
How to check the area of a parallelogram 4 x 2 = 8 cm.
2 90º base 4 cm, Cut off the piece at the dotted line.
Copyright © 2000 by Monica Yuskaitis
height 2 cm.
How to check the area of a parallelogram 4 x 2 = 8 cm.
2 90º base 4 cm, Cut off the piece at the dotted line.
Copyright © 2000 by Monica Yuskaitis
height 2 cm.
How to check the area of a parallelogram 4 x 2 = 8 cm.
2 90º base 4 cm, Move this piece to the other side.
Copyright © 2000 by Monica Yuskaitis
height 2 cm.
How to check the area of a parallelogram 4 x 2 = 8 cm.
2 90º base 4 cm, Move this piece to the other side.
Copyright © 2000 by Monica Yuskaitis
How to check the area of a parallelogram 4 x 2 = 8 cm.
2 height 2 cm.
90º base 4 cm, Now you have a rectangle 4 x 2 cm.
Copyright © 2000 by Monica Yuskaitis
How to check the area of a parallelogram 4 x 2 = 8 cm.
2 width 2 cm.
length 4 cm, What is the area of this rectangle?
Copyright © 2000 by Monica Yuskaitis
How to check the area of a parallelogram 4 x 2 = 8 cm.
2 width 2 cm.
length 4 cm, That’s right! 8 cm 2 The same as the parallelogram.
Copyright © 2000 by Monica Yuskaitis
What is the area of this parallelogram?
height 5 cm.
x
5 7 35 cm.
2 base 7 cm.
You say:
35 square centimeters
Copyright © 2000 by Monica Yuskaitis
What is the area of this parallelogram?
height 5 ft.
x
5 6 30 ft.
2 base 6 ft.
You say:
30 square feet.
Copyright © 2000 by Monica Yuskaitis
What is the area of this parallelogram?
height 10 m.
x
10 5 50 m.
2 base 5 m.
You say:
50 square meters.
Copyright © 2000 by Monica Yuskaitis