To find what we are looking for we first need to find the second equation.
To do this we need to use the equation of a line:

where (x1,y1) is a point on the line and m is the slope. The slope of a line is given by:

Using the first two points on the table we get:

Now that we have the slope we plug it in the equation of a line with the values of any of the points in the table (we are going to use the first one). Then:

Now that we have the equation of the second line we conclude that we have the system of equations:

To find the x value of the solution we solve the second equation for y, then:

now we plug this value into the first equation and solve for x:

Therefore, the x value of the solution of the system is 2.