Question

Find the equations of the diagonals of the square formed by the lines x = 0, y = 0, x = 1 and y = 1.

Answer 1

$\text{Suppose ABCD is the required square from by four vertices having diagonals AC and BD.}\text{The equation of the diagonal AC is given by}x-0=(y-0)\frac{1-0}{1-0}\Rightarrow x=y\text{The equation of the diagonal BD is given by}x-1=(y-0)\frac{1-0}{0-1}\Rightarrow x-1=-y\Rightarrow x+y=1$