More Related Content More from Jessica Garcia (20) 11.1 area of triangles and parallelograms1. AREAS OF POLYGONS
Which of the following areas are
you trying to find?
Parallelogram Triangle Trapezoid
2. AREA OF A PARALLELOGRAM
b
h
Welcome. Today you’re going to discover
the formula for area of a parallelogram.
Click to Continue
3. AREA OF A PARALLELOGRAM
b
h
To do this let’s cut the left triangle and…
Click to Continue
4. AREA OF A PARALLELOGRAM
h b
h
slide it…
Click to Continue
8. AREA OF PARALLELOGRAM
b
h
…thus, changing it to a rectangle.
What is the area of the rectangle?
A bh A b h A 2bh
10. AREA OF A PARALLELOGRAM
b
h
Since the area of the rectangle and parallelogram are
the same, just rearranged, what is the formula for the
area of this parallelogram?
A bh A b h A 2bh
12. The next slide will take
you into discovering the
area of a triangle.
Do you wish to continue?
Yes No
13. AREA OF A TRIANGLE
Hello. You will now be
discovering the formula
h for area of a triangle.
Click to Continue
b
14. AREA OF A TRIANGLE
? Let’s divide the triangle
so that we divide the
height in two.
?
b Click to Continue
15. AREA OF A TRIANGLE
Remember, we divided
the height into two equal
?
parts.
Now take the top and
rotate…
?
b Click to Continue
21. AREA OF A TRIANGLE
?
?
b
…until you have a parallelogram.
How would you represent the height of this parallelogram?
1
h 2h 2 h
22. AREA OF A TRIANGLE
?
?
?
?
b
b
Remember, you divided the height in two.
Click to Continue
23. AREA OF A TRIANGLE
?
b
What is the area of this parallelogram?
1
A bh A 2 hb A 2bh
25. AREA OF A TRIANGLE
The area of this triangle
would be the same as
the parallelogram.
Therefore, the formula for
h
the area of a triangle is…
what?
b
1
A bh A 2 hb A 2bh