Question 1040464
{{{ ( y - 4 ) / ( x - 3 ) = ( 1 - 4 ) / ( 2 - 3 ) }}}
{{{ ( y - 4 ) / ( x - 3 ) = -3/(-1) }}}
(1) {{{ ( y - 4 ) / ( x -3 ) = 3 }}}
------------------------------------
Note that I could have used ( 2,1 ) and done 
it this way, but it turns out exactly the same:
{{{ ( y - 1 ) / ( x - 2 ) = ( 4 - 1 ) / ( 3 - 2 ) }}}
(2) {{{ ( y - 1 ) / ( x - 2 ) = 3 }}}
-------------------------------------
(1) {{{ y - 4 = 3*( x - 3 ) }}}
(1) {{{ y  - 4 = 3x - 9 }}}
(1) {{{ y = 3x - 5 }}}
-----------------------
and, using (2,1 ),
(2) {{{ y - 1 = 3*( x - 2 ) }}}
(2) {{{ y - 1 = 3x - 6 }}}
(2) {{{ y = 3x - 5 }}}
------------------------
Absolutely amazing!