Question

The straight line passes through the points $(0,0)$, $(-1,1)$ and $(1,-1)$ has an equation:

• A. $2-x=3y$
• B. $y=x$
• C. $2x-y=0$
• D. $x+y=0$

Answer 1

The correct option is D

$x+y=0$

We have to check whether the given points satisfy the equations.

Putting all the points in the fourth equation:

$\begin{array}{rcl}x+y& =& 0\\ 0+0& =& 0\\ -1+1& =& 0\\ 1-1& =& 0\end{array}$

As all the given points satisfy the equation $x+y=0.$

We can see that the given points do not satisfy the other options.

Hence, option (D) is correct .