1. Quadrilaterals II
Geometry – Unit 6

2. Quadrilateral Family
parallelogram
rectangle
trapezoid
square
rhombus

3. Perimeter – (P) The distance around a figure.
Definition
Perimeter – (P) The distance around a figure. 5
9 in. 9 5
5 in.
5 in. + 9
28 in.
9 in.

4. A shortcut for the square is 4 x side.
Find the perimeter
9 cm. 9
9 cm.
9 cm. 9 9 + 9
36 cm.
9 cm.
A shortcut for the square is 4 x side.

5. Find the perimeter
7 cm. 9
9 cm.
9 cm. 7 9 + 7
36 cm.
7 cm.

6. Find the perimeter
10 ft. 10
10 ft.
10 ft. 6 10 + 10
36 ft.
6 ft.

7. Find the perimeter
18 m. 12
12 m.
15 m. 11 15 + 18
11 m.
56 m.

8. The area of this rectangle is 8 squares.
Definition
Area – (A) the measure, in square units, of the surface of a figure.
The area of this rectangle is 8 squares.

9. How to find the area of a square or rectangle.
Step 1 – Multiply the length times the
width. (A = l x w) 5 x 3
3 cm. 15
5 cm.

10. 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. 5 x 3
3 cm. 15
cm.2
5 cm.

11. How to find the area of a square or rectangle.
Step 3 – Read the answer: 15 square
centimeters. 5 x 3
3 cm. 15
cm.2
5 cm.

12. What is the area? 5 x 6
5 ft. 30
ft.2
6 ft.
You say: 30 square feet.

13. What is the area? 2
2 in. x 6 12
in.2
6 in.
You say: 12 square inches.

14. What is the area? 7
4 m. x 4 28
m.2
7 m.
You say: 28 square meters.

15. How to find the area of a parallelogram
Step 1 – Multiply the base times the
height. (A = b x h)
height
90º
base

16. How to find the area of a parallelogram
Step 1 – Multiply the base times the
height. (A = b x h) 2 13
height 17 x
13 in.
90º 9 1 + 1 3
base
17 in.
221

17. 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. 13 x 17
height 9 1
13 in.
90º 1 3 +
221
in. 2
base
17 in.

18. 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.

19. How to check the area of a parallelogram
4 x 2 = 8 cm.2
height
2 cm.
90º
base 4 cm,
Cut off the piece at the dotted line.

20. How to check the area of a parallelogram
4 x 2 = 8 cm.2
height
2 cm.
90º
base 4 cm,
Cut off the piece at the dotted line.

21. How to check the area of a parallelogram
4 x 2 = 8 cm.2
height
2 cm.
90º
base 4 cm,
Move this piece to the other side.

22. How to check the area of a parallelogram
4 x 2 = 8 cm.2
height
2 cm.
90º
base 4 cm,
Move this piece to the other side.

23. 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.

24. 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?

25. How to check the area of a parallelogram
4 x 2 = 8 cm.2
width
2 cm.
length 4 cm,
That’s right! 8 cm2 The same as
the parallelogram.

26. What is the area of this parallelogram?5
height 5 cm. x 7 35
cm.2
base 7 cm.
You say: 35 square centimeters

27. What is the area of this parallelogram?
height 5 ft. 5 x 6 30
ft.2
base 6 ft.
You say: 30 square feet.

28. What is the area of this parallelogram?
height 10 m. 10 x 5 50
m.2
base 5 m.
You say: 50 square meters.