Slide 1

Area of a Parallelograms and Triangles

Slide 2

What is the area of this parallelogram? PARALLELOGRAM B=base S=side H=height

Slide 3

What is the area of this parallelogram? PARALLELOGRAM CUT HERE! S=side H=height B=base

Slide 4

What is the area of this parallelogram? PARALLELOGRAM MOVE TO HERE! B=base H=height

Slide 5

Its the same as the area of this rectangle! PARALLELOGRAM H=height B=base

Slide 6

Area rectangle = Base x Height (perpendicular height H) PARALLELOGRAM H=height B=base

Slide 7

Area parallelogram = Base x Height (perpendicular height H) PARALLELOGRAM B=base Side H=height

Slide 8

To find the area of a parallelogram, you always multiply the base and the height. Remember: The height is the line segment that is perpendicular to the base and creates a right angle. 12 in 10 in What is the area of this parallelogram? Area = base x height A = (10)(10) A = 100 in

Slide 9

Examples Find the area of the parallelogram. 11 in

Slide 10

Your Turn Find the area of the parallelogram. 12 cm 14 cm

Slide 11

A treadmills belt is in the shape of a parallelogram before the ends are joined to form a loop. The area of the belt is 2052 in. The belts width, which is the height of the parallelogram, is 18 inches. Find the length of the belt, which is the base of the parallelogram.

Slide 12

b The length of the treadmills belt is 114 inches

Slide 13

Triangles Height and Base of a Triangle HEIGHT BASE HEIGHT BASE

Slide 14

Area of a Triangle

Slide 15

Why is that the Area of a Triangle? 1 2 Area of parallelogram = base x height

Slide 16

Finding the Area of a Triangle 1. Write the formula for area of a triangle. 2. Substitute in values. 3. Simplify. 111 ft 231 ft

Slide 17

Examples 1. Find the Area of the triangle. 2. A = ?, b = 9 ft, h = 6 ft 16.1 m 12 m

Slide 18

Finding the Base of a Triangle A triangle has a height of 10 centimeters and an area of 35 square centimeters. Find the base of the triangle. Write the formula for area of a triangle. Substitute in values. Simplify. Solve.

Slide 19

Practice: Blue Book Pg. 554: #7-13 all Pg. 561: #6-15 all