In order to find correct system for the given graph, we need to find the slopes and y-intercepts of the lines in shown graph.
For red line we have y-intercept = 10 because it is cutting y-axis at 10.
And slope of the red line is rise/run = 1/1 that is 1.
Using slope-intercept form y=mx+b
The equation of red line is y=1x +10 or x-y =-10.
For black line we have y-intercept = 6 and slope is rise/run = -1/1 = -1.
The equation of black line is y = -1x + 6 or x+y=6.
Therefore, correct option is D. x + y = 6 and x − y = -10.
