1. I can't use the 2 point to find the equation of a line. 2. The same relation,, may be regarded as either the equation of a line or the equation of a point. 3. We have two cases : " L " may be 0, or it may be the equation of a line. 4. This is the equation of a line according to the definition and the complement is called the " line at infinity ". 5. There are many variant ways to write the equation of a line which can all be converted from one to another by algebraic manipulation. 6. The point-slope form of an equation forms an equation of a line, given a point ( H, K ) and slope M. 7. The equation of a line through the origin may be written where " n " and " m " are not both 0. 8. At the section here, it gives a method for determining the equation of a line that is tangent to two circles, and says that there are " two solutions ". 9. Now, the deal is, even though you can't " picture " a line in any more than three dimensions, " the rules for writing the equation of a line still apply in any number of dimensions ".