C Program to Draw a Triangle using Graphics

#include<stdio.h>
#include<conio.h>
#include<graphics.h>
#include<math.h>
main()
{
int gd, gm, a;
gd=DETECT;
initgraph(&gd, &gm, "C:\\TC\\BGI");
printf("Enter the value of side of equilateral triangle: ");
scanf("%d", &a);
setcolor(BROWN);
moveto(150, 250);
linerel(a,0);
linerel(-a/2, -sqrt(3.0)/2*a);
lineto(150, 250);
outtextxy(20, 450, "Press any key to continue...");
getch();
closegraph();
}

Output: