7.7Perimeters and Areas of Quadrilaterals.notebook
7.5 Areas and Perimeters of Quadrilaterals
February 03, 2015
Review:
Add this together:
I CAN...
Find the perimeter and area of any quadrilateral.
Jul 24­9:36 AM
Perimeters of Quadrilaterals
What is perimeter?
­the distance around a 2­dimensional object
Feb 14­7:16 AM
3rd grade level perimeter question:
2
A
high school level perimeter question:
A
B
1
B
1
D
D
C
2
C
ABCD is a square
ABCD is a square
Perimeter = 6
Perimeter = 6
Jul 24­9:36 AM
Jul 24­9:36 AM
High School Level Perimeter Problems
Finding perimeter with missing sides lengths
Perimeters of Quadrilaterals
EX 1) Find the perimeter of parallelogram ABCD. When we are missing side lengths of a quadrilateral we will need to use various strategies to find missing those missing side lengths.
­ Pythagorean Theorem
D
Jul 24­9:36 AM
B
4
­ Special Right Triangles (30­60­90 and 45­45­90)
10
A
3
C
Jul 24­9:36 AM
1
7.7Perimeters and Areas of Quadrilaterals.notebook
Perimeters of Quadrilaterals
EX 2) Find the perimeter of isoceles trapezoid ABCD. A
7
February 03, 2015
Perimeters of Quadrilaterals
EX 3) Find the perimeter of the square ABCD. B
A
B
D
C
C
D
Jul 24­9:36 AM
Jul 24­9:36 AM
Areas of Quadrilaterals
Areas of Quadrilaterals
Formulas for finding the area:
Parallelograms (includes rectangles and squares):
Find the area of the parallelograms below.
**Remember you might have to use Pythagorean theorem or special right triangles to find missing pieces of the quadrilateral.**
EX 4)
A=base x height
7
9
height
5
A=bh
base
5
EX 5)
13
Jul 24­9:36 AM
Jul 24­9:36 AM
Areas of Trapezoids
Areas of Quadrilaterals
Formulas for finding the area:
base 1
Trapezoids:
Find the area of the trapezoids below
**Remember you might have to use Pythagorean theorem or special right triangles to find missing pieces of the quadrilateral.**
A= 21 (base 1 + base 2)xheight
height
base 2
EX 6)
1
6
4
Jul 24­9:36 AM
Jul 24­9:36 AM
2
7.7Perimeters and Areas of Quadrilaterals.notebook
February 03, 2015
Areas of Quadrilaterals
Areas of Rhombi and Kites
Find the area of the trapezoids below.
Formulas for finding the area:
**Remember you might have to use Pythagorean theorem or special right triangles to find missing pieces of the quadrilateral.**
Rhombus and Kite:
EX 7)
2
1
A= 2 (diagonal 1 x diagonal 2)
6
EX 8)
diagonal 2
12
12
12
12
EX 9)
diagonal 1
3
5
9
diagonal 2
diagonal 1
Jul 24­9:36 AM
Jul 24­9:36 AM
Feb 14­7:08 AM
3