SOLUTION: I am soo confused on how to represent numbers with matrices. Such as [3 -2 1] [2 1 -4}

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Question 137422: I am soo confused on how to represent numbers with matrices. Such as [3 -2 1]
[2 1 -4}
A=2x3
It says that the special location for -2 is 12.And that -4 is a23. I dont know how to figure those out.
I was wondering how they figured that out.
THANKS!
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
I am soo confused on how to represent numbers with matrices. Such as [3 -2 1]
[2 1 -4}
A=2x3
It says that the special location for -2 is 12.And that -4 is a23. I dont know how to figure those out.
I was wondering how they figured that out.
THANKS!

They are just two digit side by side and the first digit tells what row
a certain number is in, while the second digit tells what column that
certain number is in.
`
%28matrix%282%2C3%2C4%2C-2%2C1%2C3%2C1%2C-4%29%29
`
The special location for the 4 is called 11, which does NOT mean "eleven" even though it looks exactly like "eleven". It is read "one one" which means that 4 is in row 1 and column 1.
`
The special location for the -2 is called 12, which does NOT mean "twelve" even though it looks exactly like "twelve". It is read "one two" which means that -2 is in row 1 and column 2.
`
The special location for the upper 1 is called 13, which does NOT mean "thirteen" even though it looks exactly like "thirteen". It is read "one three" which means that the upper 1 is in row 1 and column 3.
`
The special location for the 3 is called 21, which does NOT mean "twenty-one" even though it looks exactly like "twenty-one". It is read "two one" which means that 3 is in row 2 and column 1.
`
The special location for the lower 1 is called 22, which does NOT mean "twenty-two" even though it looks exactly like "twenty-two". It is read "two two" which means that the lower 1 is in row 2 and column 2.
`
The special location for the -4 is called 23, which does NOT mean "twenty-three" even though it looks exactly like "twenty-three". It is read "two three" which means that the -4 is in row 2 and column 3.
`
Oftentimes a general matrix, say a 4x5 matrix, will be written
`
[a11 a12 a13 a14 a15]
[a21 a22 a23 a24 a25]
[a31 a32 a33 a34 a35]
[a41 a42 a43 a44 a45]
`
The two digits are written as subscripts. You might remember the word
"arc" to remember "aRC", where the R stands for the row
and the C stands for the column.
`
Edwin