Finding the area of a Trapezoid and volume and a cylendar.




To find the volume of a cylinder is quite easy if you put your mind to it. Just folow the steps below to figure out how to find the volume of a cylendar.
Formula: area of top×height=volume



external image c0838000-cylinder.jpg
Example problem:Heigh=10 raduius=3 (if you do not know what the radius is then watch the video,or look at the picture above)
Simplify the problem:
To find the area of the top you take pi×radius²=area of top (radius is half the diameter, on the top of the cylinder.)
3×3=9 which is the radius multiplyed by itself.
Now you are multiplying the two 3.14×9=28.26
Now since you already found the area of the top, you can multiply your answer by the height.
28.26× 10 =282.6
And there you have it, the volume of a cylendar!
Area of a Trapezoid:



external image trapezoid.jpg
To learn how to do the area of a trapezoid look at the folowing example problem:
side A: 5cm.
side B: 10 cm.
Height: 7cm.
Formula:¹/²×h×(A+B)=area
Simplify: PEMDAS parenthases first! 5+10=15
.5×7×15=52.5
Here is a me working out the first volume problem above.

this is a website that will help you!
http://library.thinkquest.org/20991/geo/solids.html