Hunterhill
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January 8th, 2022 at 7:03:40 PM permalink
There is a piece of land that is triangular shaped.
It is 58 meters by 55 meters by 46 meters.
The 55 meter side is frontage and has to be split at the middle point so at 29 meters.
How would the land be divided to make each piece the same area? I believe it leaves a triangle shape on one side and on the other side a 4 sided piece.
I知 stuck on this. Thanks anyone
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LoquaciousMoFW
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January 8th, 2022 at 7:23:18 PM permalink
Quote: Hunterhill

There is a piece of land that is triangular shaped.
The 55 meter side is frontage and has to be split at the middle point so at 29 meters.
link to original post


Ok, which side is split, the 55 or the 58? Also, any right angles in the original parcel? Also also, I assume you only get to use one straight line to divide the parcel?
ChesterDog
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January 8th, 2022 at 7:47:51 PM permalink
Quote: Hunterhill

There is a piece of land that is triangular shaped.
It is 58 meters by 55 meters by 46 meters.
The 55 meter side is frontage and has to be split at the middle point so at 29 meters.
How would the land be divided to make each piece the same area? I believe it leaves a triangle shape on one side and on the other side a 4 sided piece.
I知 stuck on this. Thanks anyone
link to original post



To bisect the area of a triangle, just cut along a line from any vertex to the midpoint of the opposite side.

The area of a triangle equals one-half its base times its height. You can see in the diagram that both smaller triangles have the same base length and the same height. Therefore, they are equal in area.

Hunterhill
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January 8th, 2022 at 8:20:19 PM permalink
Quote: ChesterDog

Quote: Hunterhill

There is a piece of land that is triangular shaped.
It is 58 meters by 55 meters by 46 meters.
The 55 meter side is frontage and has to be split at the middle point so at 29 meters.
How would the land be divided to make each piece the same area? I believe it leaves a triangle shape on one side and on the other side a 4 sided piece.
I知 stuck on this. Thanks anyone
link to original post



To bisect the area of a triangle, just cut along a line from any vertex to the midpoint of the opposite side.

The area of a triangle equals one-half its base times its height. You can see in the diagram that both smaller triangles have the same base length and the same height. Therefore, they are equal in area.


link to original post

Thanks Chester, how do I find out the height of the triangle
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ChesterDog
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January 8th, 2022 at 9:02:34 PM permalink
Quote: Hunterhill

Quote: ChesterDog

Quote: Hunterhill

There is a piece of land that is triangular shaped.
It is 58 meters by 55 meters by 46 meters.
The 55 meter side is frontage and has to be split at the middle point so at 29 meters.
How would the land be divided to make each piece the same area? I believe it leaves a triangle shape on one side and on the other side a 4 sided piece.
I知 stuck on this. Thanks anyone
link to original post



To bisect the area of a triangle, just cut along a line from any vertex to the midpoint of the opposite side.

The area of a triangle equals one-half its base times its height. You can see in the diagram that both smaller triangles have the same base length and the same height. Therefore, they are equal in area.

...
link to original post

Thanks Chester, how do I find out the height of the triangle
link to original post



In this diagram, the height h equals 46 sin C.

To find C,we apply the "Law of Cosines," which is c2 = a2 + b2 - 2ab cos C.

Rearrange this to: cos C = (a2 + b2 - c2) / (2ab)

Let a = 46, b = 58, and c = 55, then cos C is about 0.46008. And sin C equals the square root of 1 - cos2C, which is about 0.88788.

So, the height is about 46(0.88788) = 40.8423.

Hunterhill
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January 8th, 2022 at 9:09:12 PM permalink
Thanks Chester. I found something called Herron痴 formula online which I think is basically what you did.
Greatly appreciated.
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SOOPOO
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January 9th, 2022 at 4:44:13 AM permalink
Quote: Hunterhill

There is a piece of land that is triangular shaped.
It is 58 meters by 55 meters by 46 meters.
The 55 meter side is frontage and has to be split at the middle point so at 29 meters.
How would the land be divided to make each piece the same area? I believe it leaves a triangle shape on one side and on the other side a 4 sided piece.
I知 stuck on this. Thanks anyone
link to original post



I think there is a typo? Did you mean to say the 58 meter side is frontage, not the 55 meter side? Splitting 55 meters would be 27.5, not 29.
OnceDear
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January 9th, 2022 at 5:24:45 AM permalink
Quote: ChesterDog

Quote: Hunterhill

Quote: ChesterDog


To bisect the area of a triangle, just cut along a line from any vertex to the midpoint of the opposite side.

The area of a triangle equals one-half its base times its height. You can see in the diagram that both smaller triangles have the same base length and the same height. Therefore, they are equal in area.

...
link to original post

Thanks Chester, how do I find out the height of the triangle
link to original post



In this diagram, the height h equals 46 sin C.

To find C,we apply the "Law of Cosines," which is c2 = a2 + b2 - 2ab cos C.

Rearrange this to: cos C = (a2 + b2 - c2) / (2ab)

Let a = 46, b = 58, and c = 55, then cos C is about 0.46008. And sin C equals the square root of 1 - cos2C, which is about 0.88788.

So, the height is about 46(0.88788) = 40.8423.


link to original post

Fact is that you don't need to know the height. the two triangles formed reach the same peak, so have same height. They have same base width. Area=1/2 x base x height. So same area. All you needed to do was work out the mid point in the frontage.
Psalm 25:16 Turn to me and be gracious to me, for I am lonely and afflicted. Proverbs 18:2 A fool finds no satisfaction in trying to understand, for he would rather express his own opinion.
Hunterhill
Hunterhill
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January 9th, 2022 at 6:35:09 AM permalink
Quote: SOOPOO

Quote: Hunterhill

There is a piece of land that is triangular shaped.
It is 58 meters by 55 meters by 46 meters.
The 55 meter side is frontage and has to be split at the middle point so at 29 meters.
How would the land be divided to make each piece the same area? I believe it leaves a triangle shape on one side and on the other side a 4 sided piece.
I知 stuck on this. Thanks anyone
link to original post



I think there is a typo? Did you mean to say the 58 meter side is frontage, not the 55 meter side? Splitting 55 meters would be 27.5, not 29.
link to original post


Yes that was a typo I meant the frontage was 58.
Last edited by: unnamed administrator on Jan 9, 2022
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ThatDonGuy
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ChesterDog
January 9th, 2022 at 6:54:20 AM permalink
Quote: OnceDear



There are (at least) two other ways to calculate h.

First, let x be the distance from the left end of the 58-side to where the altitude intersects it; the distance from the right end is 58-x.
Solve for x using the Pythagorean Theorem twice:
h^2 = 55^2 - x^2 = 46^2 - (58 - x)^2
55^2 - x^2 = 46^2 - 58^2 + 116 x - x^2
55^2 - 46^2 + 58^2 = 116 x
x = 4273 / 116
h = sqrt(55^2 - (4273 / 116)^2) = 40.8423

Second, one formula for the area of a triangle with side lengths A, B, C, is sqrt(S (S-A) (S-B) (S-C)), where S = (A + B + C) / 2.
In this case, S = 159/2, so Area = sqrt(159/2 * 49/2 * 67/2 * 43/2) = 7 sqrt(458,079) / 4
Area = 1/2 * 58 * h = 29 h, so h = Area / 29 = 40.8423
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