Download presentation

1
Area of Triangles

2
**A = 40 cm² The area of this rectangle is 40 cm².**

If you divide this rectangle in half, what two shapes do you see? A = 40 cm²

3
**A = 40 cm² A = 20 cm² The area of this rectangle is 40 cm².**

If you divide this rectangle in half, what two shapes do you see? Triangles So if the rectangle’s area is 40 cm², what is ½ of the rectangle’s area? 20 cm² A = 40 cm² A = 20 cm²

4
**A = 64 cm² The area of this parallelogram is 64 cm².**

If you divide this parallelogram in half, what two shapes do you see? A = 64 cm²

5
**A = 64 cm² A = 32 cm² The area of this parallelogram is 64 cm².**

If you divide this parallelogram in half, what two shapes do you see? Triangles So if the parallelogram’s area is 64 cm², what is ½ of the parallelogram’s area? 32 cm² A = 64 cm² A = 32 cm²

6
**Area A = 8 cm × 5 cm A = 40 cm² A = ½ × 8 cm × 5 cm A = 4 cm × 5 cm A**

Since triangles are ½ of a rectangle or parallelogram, the formula for finding the area of triangles is A = ½bh. A = 8 cm × 5 cm A = 40 cm² A = × 8 cm × 5 cm A = 4 cm × 5 cm A = 20 cm²

7
**Area A = 8 cm × 8 cm A = 64 cm² A = ½ × 8 cm × 8 cm A = 4 cm × 8 cm A**

Since triangles are ½ of a rectangle or parallelogram, the formula for finding the area of triangles is A = ½bh. A = 8 cm × 8 cm A = 64 cm² A = × 8 cm × 8 cm A = 4 cm × 8 cm A = 32 cm²

8
**Area of a Triangle ½ A = × 6 cm × 3 cm A = 3 cm × 3 cm A = 9 cm² ½ A =**

If you know the base (b) and the height (h) of a triangle, you can use a formula to find its area. If you multiply the ½ × b × h, you get the area (A). A = ½ × b × h or A = ½bh A = × 6 cm × 3 cm A = 3 cm × 3 cm A = 9 cm² A = × 4 cm × 5 cm A = 2 cm × 5 cm A = 10 cm² A = × 6 cm × 7 cm A = 3 cm × 7 cm A = 21 cm² © 2007 M. Tallman

9
**( ) 4 x 3 x 2 = 24 (4 × 3) × 2 = 4 × (3 × 2) Associative Property**

The way the factors are grouped does not change the product. The associative property can make finding the area of a triangle easier! ( ) 4 x 3 x 2 = 24 (4 × 3) × 2 = 4 × (3 × 2)

10
**A = ( ) ½ × b × h (½ × b) × h = ½ × (b × h) = (½ × h) × b**

Associative Property The way the factors are grouped does not change the product. The associative property can make finding the area of a triangle easier! A = ( ) × b × h (½ × b) × h = ½ × (b × h) = (½ × h) × b Group the factors in which ever way that makes the problem easier to solve.

11
**Use the formula A = ½bh to find the area of the triangle.**

(½ × 8 ft) × 9 ft A = 4 ft × 9 ft A = 36 ft²

12
**Use the formula A = ½bh to find the area of the triangle.**

14 yd 20 yd A = (½ × 20 yd) × 14 yd A = 10 yd × 14 yd A = 140 yd²

13
**Use the formula A = ½bh to find the area of the triangle.**

(½ × 16 m) × 9 m A = 8 m × 9 m A = 72 m²

14
**Use the formula A = ½bh to find the area of the triangle.**

½ × 7 in × 10 in A = 7 in × 5 in A = 35 in²

15
**Use the formula A = ½bh to find the area of the triangle.**

6 mm 11 mm A = ½ × (11 mm × 6 mm) A = 11 mm × 6 mm A = 33 mm²

16
Find the Area A = 36 units²

17
Find the Area A = 27.5 units²

18
Find the Area A = 24 units²

19
Find the Area A = 20 units²

20
Find the Area A = 9 units²

21
Find the Area A = 16 units²

22
Find the Area A = 21 units²

23
**Find the Missing Measurement**

A = 24 mm² 24 mm² × 2 = 48 mm² 48 mm² ÷ 8 mm = 6 mm 8 mm b 6 mm

24
**Find the Missing Measurement**

A = 59.5 ft² 8.5 ft h 14 ft 59.5 ft² × 2 = 119 ft² 119 ft² ÷ 14 ft = 8.5 ft

25
**Find the Missing Measurement**

A = 54 in² 9 in 12 in b 54 in² × 2 = 108 in² 108 in² ÷ 9 in = 12 in

26
**Find the Missing Measurement**

A = ft² h 11.5 ft 7 ft 40.25 ft² × 2 = 80.5 ft² 80.5 ft² ÷ 7 ft = 11.5 ft

27
**Find the Missing Measurement**

A = 48 yd² 48 yd² × 2 = 96 yd² 96 yd² ÷ 12 yd = 8 yd 12 yd 8 yd b

Similar presentations

OK

Using Lowest Common Denominator to add and subtract fractions

Using Lowest Common Denominator to add and subtract fractions

© 2018 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on business plan on restaurant Ppt on ip addresses class and range Ppt on social media past present and future Ppt on internet as a post office Edit ppt online Ppt on law against child marriage in india Ppt on job evaluation examples Ppt on project rhino in indian Ppt on the road not taken symbolism Ppt on fdi and fii