# Visual C++ - Finding the equation of a Line Given Two End Points

Here is the Visual C++ program for finding the equation of a Line Given Two End Points (x1,y1) and (x2, y2)

The equation for a line is Y = MX + C

Where M = Slope of a Line and C = Intercept

To Find the slope of a line

slope = (y2 - y1) / (x2 - x1)

To Find the intercept of the line, intercept = y1 - (slope) * x1

which would be same as, intercept = y2 - (slope) * x2

## Source Code

#include <iostream>

#include <math.h>

void main()

{

float slope, intercept;

float x1, y1, x2, y2;

float dx, dy;

std::cout << "Program to find the equation of a line given two end points\n";

std::cout << "Enter X1: ";

std::cin >> x1;

std::cout << "Enter Y1: ";

std::cin >> y1;

std::cout << "Enter X2: ";

std::cin >> x2;

std::cout << "Enter Y2: ";

std::cin >> y2;

dx = x2 - x1;

dy = y2 - y1;

slope = dy / dx;

// y = mx + c

// intercept c = y - mx

intercept = y1 - slope * x1; // which is same as y2 - slope * x2

std::cout << "Equation of the line with end points (" << x1 << ", " << y1 << ") and (" << x2 << ", " << y2 << ") : Y = ";

std::cout << slope << "X " << ((intercept < 0) ? ' ' : '+') << intercept << "\n";

}

## Output

Program to find the equation of a line given two end points

Enter X1: 2

Enter Y1: 3

Enter X2: 5

Enter Y2: 7

Equation of the line with end points (2, 3 and (5, 7) : Y = 1.33333X +0.333333

Press any key to continue . . .