To see this we are going to evaluate the equations in the point, taking in count that x = 2 and y = -3 because the point is (2, -3), now for the fist equation we have that
[tex]y\text{ = }2(2)\text{ - 7 = }4\text{ - 7 = -3}[/tex]So for the fisrt equation the point is a solution.
Now for the second equation we have that
[tex]-1x\text{ + 1y = }-1(2)\text{ + 1(-3) = -2 -3 = -5}[/tex]So for the second equation the point is a solution. Then for both equations the point is a solution.
