Ad
related to: triangle area calculator using coordinates and slope given points
Search results
Results From The WOW.Com Content Network
The area of a triangle can be demonstrated, for example by means of the congruence of triangles, as half of the area of a parallelogram that has the same base length and height. A graphic derivation of the formula T = h 2 b {\displaystyle T={\frac {h}{2}}b} that avoids the usual procedure of doubling the area of the triangle and then halving it.
For any choice of trilinear coordinates x : y : z to locate a point, the actual distances of the point from the sidelines are given by a' = kx, b' = ky, c' = kz where k can be determined by the formula = + + in which a, b, c are the respective sidelengths BC, CA, AB, and ∆ is the area of ABC.
See: Area of a triangle § Using coordinates. The expression is equivalent to h = 2 A b {\textstyle h={\frac {2A}{b}}} , which can be obtained by rearranging the standard formula for the area of a triangle: A = 1 2 b h {\textstyle A={\frac {1}{2}}bh} , where b is the length of a side, and h is the perpendicular height from the opposite vertex.
The area formula for a triangle can be proven by cutting two copies of the triangle into pieces and rearranging them into a rectangle. In the Euclidean plane, area is defined by comparison with a square of side length , which has area 1. There are several ways to calculate the area of an arbitrary triangle.
In this example, the triangle's side lengths and area are integers, making it a Heronian triangle. However, Heron's formula works equally well when the side lengths are real numbers. As long as they obey the strict triangle inequality, they define a triangle in the Euclidean plane whose area is a positive real number.
In fact, given any point in cartesian coordinates, we can use this fact to determine where this point is with respect to a triangle. If a point lies in the interior of the triangle, all of the Barycentric coordinates lie in the open interval ( 0 , 1 ) . {\displaystyle (0,1).}
Slope illustrated for y = (3/2)x − 1.Click on to enlarge Slope of a line in coordinates system, from f(x) = −12x + 2 to f(x) = 12x + 2. The slope of a line in the plane containing the x and y axes is generally represented by the letter m, [5] and is defined as the change in the y coordinate divided by the corresponding change in the x coordinate, between two distinct points on the line.
The three altitudes of a triangle intersect at the orthocenter, which for an acute triangle is inside the triangle. The orthocenter of a triangle, usually denoted by H, is the point where the three (possibly extended) altitudes intersect. [1] [2] The orthocenter lies inside the triangle if and only if the triangle is acute.