1. G4.6 Area of a square, rectangle and trapezoid
Objectives:
Review definition of a trapezoid
Review formula for midsegment
Discover area formula

2. Concept: Trapezoids: base ht base
Bases: are the two sides that are parallel
base
height: is measurement of the line that is perpendicular (forms a 900 angle) to one of the bases. ht ht
base

3. Concept: Area of a Trapezoid
Recall: The mid-segment of a trapezoid
was found by taking the average of the bases.
b1 + b2 2
The area formula just
adds one additional
step. Multiply by the
height

4. Ex 1
14 in.
8 in.
22 in.
34 in.

5. Ex 2
14 in.
11 km
6.5 km
12.5 km

6. Ex 4 28 16 11 19 5 Base lines Are Parallel ht is Perpendicular to base
Trapezoid #1
Trapezoid #2
Add both
Areas
Together!

7. Concept: Let’s Try ANSWER: 53,240 mi2
Find the approximate area of Arkansas.
ANSWER:
53,240 mi2

8. Find the area of the trapezoid.
Your Turn:
Find the area of the trapezoid. 1.
ANSWER
63 m2

9. Your Turn: 1. A = 77 ft2 ANSWER h = 7 ft
A gives the area of the trapezoid. Find the missing measure. 1.
A = 77 ft2
ANSWER
h = 7 ft

10. Your Turn: 2. A = 39 cm2 ANSWER b1 = 5 cm
A gives the area of the trapezoid. Find the missing measure. 2.
A = 39 cm2 4.
ANSWER
b1 = 5 cm

12. The End Homework: PM 5.8