<PRE><B>Question 1082384</B>
&lt;pre&gt;&lt;b&gt;
Start with this:

{{{matrix(1,3,

y-y[1],
&quot;&quot;=&quot;&quot;,
m(x-x[1]))}}}

Substitute -2 for m
Substitute 4 for x&lt;sub&gt;1&lt;/sub&gt;
Substitute -1 for y&lt;sub&gt;1&lt;/sub&gt;
Do not substitute anything for x, but just leave it as x.
Do not substitute anything for y, but just leave it as y.
Simplify what you get
Solve the equation for y.

Edwin&lt;/pre&gt;</PRE>