Question 1105435
<pre>
You did not tell us what matrices A and B repesent, just what 
the sum A+B was.  So there are many possibilities.  If fact 
there are an infinite number of possibilities.  Here's one 
possibility:

{{{matrix(1,9,

A,""="",(matrix(2,1,3,-2)),",","","",B,""="",(matrix(2,1,-5,1)))}}}

As you see their sum is as you stated:

{{{matrix(1,13,

A,
""+"",
B,
"",
""="",
"",
(matrix(2,1,3,-2)),
""+"",
(matrix(2,1,-5,1)),
"",
""="",
"",
(matrix(2,1,-2,1))
)}}}

So in this one case

{{{matrix(1,19,

3A,
""+"",
2B,
"",
""="",
"",
3*(matrix(2,1,3,-2)),
""+"",
2*(matrix(2,1,-5,1)),
"",
""="",
"",
(matrix(2,1,9,-6)),
""+"",
(matrix(2,1,-10,2)),
"",
""="",
"",
(matrix(2,1,-1,-4))

)}}}

But that's just one of trillions of possibilities.

Edwin</pre>