- #1
This is the formula for finding the area of a circle, where r is the radius.
In summary, the group discusses different approaches to finding the area of a semi-circle and suggests using the concept of similarity or dividing the area of the larger semi-circle by two. They also mention using the equation A=\frac{1}{2}\left(\frac{\pi}{2}(14\text{ cm})^2\right)=49\pi\text{ cm}^2\approx154\text{ cm}^2 as a solution.
- #2
I like Serena
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susanto3311 said:
Hey! ;)
It looks like a big half circle from which 2 smaller half circles are removed.
Let's start with those.
Can you tell what their radius's are? (Wondering)
- #3
MarkFL
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Another approach would be to utilize the concept of similarity. The two smaller semi-circles have linear measures that are one-half that of the corresponding measures of the larger semi-circle, so we know their areas must each be one-fourth that of the larger. Since there are two of them, we then know the combined areas of the two smaller semicircles is one half that of the larger. So, find the area of the larger, and cut it in half (divide by two) and you will have the area in question. :D
- #4
- #5
MarkFL
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You want to find half of the area of the semi-circle...it appears you have found the area of the semi-circle...
edit: nevermind...it was unclear at first that you have divided by 2 twice...you should only use the equal sign to equate 2 quantities that are equal. :D
edit: nevermind...it was unclear at first that you have divided by 2 twice...you should only use the equal sign to equate 2 quantities that are equal. :D
- #6
susanto3311
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could you make more simple?...
- #7
MarkFL
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More simple than finding half the area of a semi-circle? No. :D
- #8
susanto3311
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how about...
= 308/2 = 154 cm2
it's true...??
= 308/2 = 154 cm2
it's true...??
- #9
MarkFL
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I would write:
\(\displaystyle A=\frac{1}{2}\left(\frac{\pi}{2}(14\text{ cm})^2\right)=49\pi\text{ cm}^2\approx154\text{ cm}^2\)
\(\displaystyle A=\frac{1}{2}\left(\frac{\pi}{2}(14\text{ cm})^2\right)=49\pi\text{ cm}^2\approx154\text{ cm}^2\)
FAQ: This is the formula for finding the area of a circle, where r is the radius.
1) How do you calculate the total area when given multiple circles?
To find the area of multiple circles, you first need to calculate the area of each individual circle using the formula A = πr². Then, add up all of the individual areas to get the total area of the multiple circles.
2) Can you find the area of multiple circles with different radii?
Yes, you can still find the total area of multiple circles with different radii. Simply use the formula A = πr² for each circle and then add up the individual areas.
3) What if the circles overlap? How do you find the area of the overlapping regions?
If the circles overlap, you will need to subtract the area of the overlapping regions from the total area. You can do this by calculating the area of the overlapping regions using the formula for the area of a segment of a circle, A = r²(arccos((d²+r²-R²)/(2dr)) - (d/2)sqrt(R²-d²), where d is the distance between the centers of the circles and R and r are the radii of the larger and smaller circles, respectively.
4) Is there a specific formula for finding the area of multiple circles with the same radius?
Yes, if all of the circles have the same radius, you can use the formula A = πr²n, where r is the radius and n is the number of circles. This formula is derived by finding the area of one circle and then multiplying it by the number of circles.
5) Can you find the area of multiple circles in 3D space?
Yes, you can find the total area of multiple circles in 3D space. In addition to the area on the xy-plane, you will also need to consider the area on the xz-plane and the yz-plane. The total area can be calculated using the formula A = 2πr(R + n), where r is the radius, R is the distance from the center of the circles to the edge of the circles, and n is the number of circles.