There are two ways to do this.
The first is you plug in the x-value from the point in the table and see if that gives you the y-value from the same point.
For example, your first point is (5,49), so plug in x=5:
y = -5(5)+2 = -25+2 = -23
Since that's not the y-value in (5,49), then (5,49) is not a solution for the equation.
The other option is you plug in both the x-value and the y-value to see if you get a true statement. (A solution will make the equaiton a true statement.)
For example, the first point is (5,49), so you'd plug in x=5 and y=49:
49 = -5(5)+2
49 = -25 + 2
49 = -23
Since that's not true, (5,49) is not a solution.
You'll notice you're basically doing the same thing, it's just whether you plug in one value or both and that's your choice.