You mean you just want to find the equation of the line?
Theoretically a line is determined by two points. Any (non-vertical) line can be written in the form y= ax+ b. Take two points and put their x, y values into that to get two equations for a and b. Since both will have "+b", subracting one equation from the other will immediately eliminate b and give you a single equation to solve for a. Put that value of a back into either equation and solve for b.
Practically, since those points are NOT on a perfect line, different choices of the two points will give different equations. You can get the most accurate line by using the two points at opposite ends.