How do I calculate a triangle coordinate?

  • Thread starter Thread starter RiaanSwiegers
  • Start date Start date
  • Tags Tags
    Coordinate Triangle
AI Thread Summary
To calculate the third corner of a triangle when two corners and the area are known, it's important to understand that the solution is not a single coordinate but rather a function describing a locus of possible coordinates. The area of triangle ABC is given as 14994 sqm, with coordinates for corners B and C provided. The calculation involves using the cross product formula, Area = 1/2 |AB × AC|, to derive the relationship between the points. This means there are infinitely many possible coordinates for corner A that satisfy the area condition, typically forming a bounded curve. Understanding this concept is crucial for solving the problem accurately.
RiaanSwiegers
Messages
1
Reaction score
0
1. Calculate the coordinate of a triangle's 3rd corner when 2 corner coordinates and area is given (in Surveying).
Given:
Area of triangle ABC = 14994sqm
Corner B coordinate = +3541.620 (Y); -5467.650 (X)
Corner C coordinate = +3300.580 (Y); -5503.150 (X)

Calculate corner A's coordinates?
I know how to calculate the area of a triangle by using the 3 coordinates, but for some or other reason the reverse of this equation doesn't work?
 
Last edited:
Physics news on Phys.org
I've been away from math too long to actually sit down and DO this problem, but the one thing that you seem to be not understanding, based on your statement of the problem, is that there is no single coordinate. That is, the answer is not a coordinate. The answer is a function describing the locus of the 3rd coordinate, of which there are an infinite number (although they might be on a bounded curve).
 
If you know how to work with cross product you can use the formula:

Area=\frac{1}{2}|AB \times AC|

But the answer will be a function.
 
Back
Top