Question

Find an equation of the line L.

Short answer

The equation of line is$y=-x+3$

Step-by-step solution

Step 1. Given Information

The given graph is

Step 2. Explanation 

From the given figure, we know the line is parallel to line $y=-x$

On comparing with the equation of line, we get the slope of line as $-1$and as lines are parallel so the slope of the other line will also be$-1$.

Substitute the values in the general form of equation of slope- line format.

$$\begin{gathered} y-y_1=m(x-x_1) \\ y-2=-1(x-1) \\ y-2=-x+1 \\ y=-x+3 \end{gathered}$$