Can someone please explain to me how this is wrong????
|dw:1404946673527:dw| \(\bf \textit{area of a segment of a circle}=\cfrac{{\color{brown}{ r}}^2}{2}\left(\cfrac{{\color{brown}{ \theta}}r}{180}-sin({\color{brown}{ \theta}})\right)\)
I found the area of the hole circle which is 153.93804 then i multiplied that by 35 which is 5387.831 then i did 5387.831/360 which equals 14.96619?
Then i rounded to the nearest hole number which is 15
|dw:1404946978668:dw|
you're correct, is 14.9 which rounds to 15, yes, for the "sector" of the circle
Ok when i plug the numbers into the equation up there i get .787535? is that right?
hmmm wait a sec... I missed something there
hmmm no .... shoot.. just have a typol lemme fix that quick
\(\bf \textit{area of a segment of a circle}=\cfrac{{\color{brown}{ r}}^2}{2}\left(\cfrac{{\color{brown}{ \theta}}\pi}{180}-sin({\color{brown}{ \theta}})\right) \\ \quad \\ \implies \cfrac{{\color{brown}{ 7}}^2}{2}\left(\cfrac{{\color{brown}{ 35^o}}\cdot \pi}{180}-sin({\color{brown}{ 35^o}})\right)\)
as jdoe shows, the *segment* is the part of the sector cut off by a chord
Another "formula" is to subtract off the area of the isosceles triangle with sides 7 and vertex angle 35º (a bit complicated, because you must use trig, but it's easier to remember, than the formula posted up above)
Ok thanks
yw
the triangle has an altitude of 7 cos(35/2) and base 2*7*sin(35/2) and area 7*7*sin(35/2)*cos(35/2) and if you know sin(2x) = 2 sin(x)cos(x) ½*7*7*sin(35)
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