import java.util.Scanner;

public class Geometry

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$/**$

Computes the area of a triangle

@param x$1$ the x$-$coordinate of the first corner

@param y$1$ the y$-$coordinate of the first corner

@param x$2$ the x$-$coordinate of the second corner

@param y$2$ the y$-$coordinate of the second corner

@param x$3$ the x$-$coordinate of the third corner

@param y$3$ the y$-$coordinate of the third corner

@return the area of the triangle

$*/$

public static double triangleArea$($double x$1,$ double y$1,$ double x$2,$ double y$2,$ double x$3,$ double y$3)$

$\{$