Answer:
2 (x_2-x_1) + 2(y_2-y_1)
Explanation:
Length of rectangle = l ( say )
=> l = √(x_1 - x_2)² + (y_2-y_2)²
=> l = √(x_1-x_2)² = x_1 - x_2 / x_2 - x_1
Let breadth = b ,
=> b = √(x_1-x_1)² + (y_2-y_2)²
=> b = y_2-y_1
So , perimeter will be ,
2(l + b)
2 (x_2-x_1) + 2(y_2-y_1)