How do you calculate vmax value?

How do you calculate vmax value?
This was on a previous question..its not my answer but it's right!!

"Basically you take all the values in this table ([S]), divide 1 by them (i.e. 1/0.10, 1/0.192), and make a new table with those values. This table should give you a linear slope, which you can use to calculate earlier values. 1/Vmax is going to be the Y intercept, or the value at which (1/[S]) = 0. So you use the linear slope to determine what 1/V is when 1/S=0, then take that value of 1/V and reverse it by dividing it by 1 to get (1/(1/V) when 1/S = 0). This will give you your Vmax