Matrix addition, subtraction

Create a square matrix at mots 3X3. Then you can multiply it by a scalar, or scare it, or calculate its determinant, and inverse. With two matrices that have the same dimensions you can perform .additions/subtractions or multiplications.

Is it complex or matrix? You can have only one mode at a time.What kind of equations? The solve function uses real-valued equations.
Complex numbers: You can add, subtract, multiply and divide. You can convert a number from rectangular to polar forms and vice-versa; you can calculate the absolute value of a complex number, or a conjugate.
All the operations are done in the Mode CMPLX.

1. First you must set Matrix calculation: Press [MODE][6:Matrix].
2. Then by entering one of the numbers [1:MatA] or [2:Matb] or [3:MatC] you get to choose the dimensions of the matrix (mxn].
3. Once finished entering the matrix you clear the screen.
4. The operations on A SINGLE matrix are available by pressing [Shift][Matrix].
   
5. The choices are
   

• [1:Dim] to change the dimension of a matrix (in fact redefining the matrix)
• [2:Data] enter values in a matrix
• [3:MatA] access Matrix A
• [4:MatB] access Matrix B
• [5:MatC] access matrix C
• [6:MatAns] access the Answer Matrix (the last matrix calculated)
• [7:det] Calculate the determinant of a matrix already defined
• [8:Trn] The transpose of a matrix already defined

Once you have created a square matrix, for example matA.
You press [Shift][Matrix] [7:det] [SHIFT][MATRIX][3:MatA], close the parenthesis and press [ENTER].

If you have defined two similar matrices (same number of row and same number of columns) you can ADD them or subtract them. The operation keys are Plus and Minus as for any number.
To multiply you use the multiplication sign. The matrices must be compatible (mxn) multiplied by (nxk).

Here is an account of what you can do with matrices on this scientific calculator. Certain precautions must be taken as concerns the dimensions of the matrices. Refer to your text book on matrix algebra.
On this calculator the largest matrices you can define have dimensions 3X3.

1. First you must set Matrix calculation: Press [MODE][6:Matrix].
2. Then by entering one of the numbers [1:MatA] or [2:Matb] or [3:MatC] you get to choose the dimensions of the matrix (mxn].
3. Once finished entering the matrix you clear the screen.
4. The operations on A SINGLE matrix are available by pressing [Shift][Matrix].
   
5. The choices are
   

• [1:Dim] to change the dimension of a matrix (in fact redefining the matrix)
• [2:Data] enter values in a matrix
• [3:MatA] access Matrix A
• [4:MatB] access Matrix B
• [5:MatC] access matrix C
• [6:MatAns] access the Answer Matrix (the last matrix calculated)
• [7:det] Calculate the determinant of a matrix already defined
• [8:Trn] The transpose of a matrix already defined

Once you have created a square matrix, for example matA.
You press [Shift][Matrix] [7:det] [SHIFT][MATRIX][3:MatA], close the parenthesis and press [ENTER].

If you have defined two similar matrices (same number of row and same number of columns) you can ADD them or subtract them. The operation keys are Plus and Minus as for any number.
To multiply you use the multiplication sign. The matrices must be compatible (mxn) multiplied by (nxk).

This post is rather exhaustive as regards the matrix capabilities of the calculator. So if the post recalls things you already know, please skip them. Matrix multiplication is at the end. As to division of matrices, I do not believe that this operation exits.

Let me explain how to create matrices. (If you know how to do it, skip to the operations on matrices, at the end.)

First you must set Matrix calculation
[MODE][6:Matrix]. Then By entering one of the numbers [1:MatA] or [2:Matb] or [3:MatC] you get to choose the dimensions of the matrix
(mxn]. Once finished entering the matrix you clear the screen.

The operations on matrices are available by pressing [Shift][Matrix]
[1:Dim] to change the dimension of a matrix (in fact redefining the matrix)
[2: D A T A] enter values in a matrix
[3:MatA] access Matrix A
[4:Matb] access Matrix B
[5:MatC] access matrix C
[6:MatAns] access the Answer Matrix (the last matrix calculated)
[7:det] Calculate the determinant of a matrix already defined
[8:Trn] The transpose of a matrix already defined

To add matrices MatA+MatB (MUST have identical dimensions same m and same n, m and n do not have to be the same)
To subtract MatA-MatB. (MUST have identical dimensions, see above)
To multiply MatAxMatB (See below for conditions on dimensions)
To raise a matrix to a power 2 [x2], cube [x3]
To obtain inverse of a SQUARE MatA already defined MatA[x^-1]. The key [x^-1] is the x to the power -1 key. If the determinant of a matrix is zero, the matrix is singular and its inverse does not exit.

Dimensions of matrices involved in operations must match. Here is a short summary

The multiplication of structured mathematical entities (vectors, complex numbers, matrices, etc.) is different from the multiplication of unstructured (scalar) mathematical entities (regular numbers). As you well know matrix multiplication is not commutative> This has to do with the dimensions.

An mXn matrix has m rows and n columns. To perform multiplication of an kXl matrix by an mXn matrix you multiply each element in one row of the first matrix by a specific element in a column of the second matrix. This imposes a condition, namely that the number of columns of the first matrix be equal to the number of rows of the second.
Thus, to be able to multiply a kXl matrix by am mXn matrix, the number of columns of the first (l) must be equal to the number of rows of the second (m).

So MatA(kXl) * MatB(mXn) is possible only if l=m
MatA(kX3) * Mat(3Xn) is possible and meaningful, but
Mat(kX3) * Mat(nX3) may not be possible.

To get back to your calculation, make sure that the number of columns of the first matrix is equal to the number of rows of the second. If this condition is not satisfied, the calculator returns a dimension error. The order of the matrices in the multiplication is, shall we say, vital.

I will not try to guess what you mean by "solve a matrix", but I believe that what follows will help you.

1. First you must set Matrix calculation: Press [MODE][6:Matrix].
2. Then by entering one of the numbers [1:MatA] or [2:Matb] or [3:MatC] you get to choose the dimensions of the matrix (mxn].
3. Once finished entering the matrix you clear the screen.
4. The operations on A SINGLE matrix are available by pressing [Shift][Matrix].
   
5. The choices are
   

• [1:Dim] to change the dimension of a matrix (in fact redefining the matrix)
• [2:Data] enter values in a matrix
• [3:MatA] access Matrix A
• [4:MatB] access Matrix B
• [5:MatC] access matrix C
• [6:MatAns] access the Answer Matrix (the last matrix calculated)
• [7:det] Calculate the determinant of a matrix already defined
• [8:Trn] The transpose of a matrix already defined

Once you have created a square matrix, for example matA.
You press [Shift][Matrix] [7:det] [SHIFT][MATRIX][3:MatA], close the parenthesis and press [ENTER].

If you have defined two similar matrices (same number of row and same number of columns) you can ADD them or subtract them. The operation keys are Plus and Minus as for any number.
To multiply you use the multiplication sign. The matrices must be compatible (mxn) multiplied by (nxk).

If you know the theory behind systems of linear equations you can use matrices to solve the systems.

I am afraid that "find the solution of a matrix" does not mean anything. However if you want to perform some arithmetic operations on the matrices ( multiplication, addition, subtraction) you can do so using the regular operation keys.
If on the other hand you want to calculate determinants of square matrices, inverse square matrices etc.
Go to the RUN/MAT screen and press [OPTN, then press F2 to open access these operations and this is what you see.

F1 type the MAT identifier in command line
M>L converts a matrix to a list
Det calculates the Determinant of a square matrix
Trn transposes the matrix,
etc.
To invert a square matix, use the [X^-1] key e.g. MatA^-1

1. First you must set Matrix calculation: Press [MODE][6:Matrix].
2. Then by entering one of the numbers [1:MatA] or [2:Matb] or [3:MatC] you get to choose the dimensions of the matrix (mxn].
3. Once finished entering the matrix you clear the screen.
4. The operations on A SINGLE matrix are available by pressing [Shift][Matrix].
   
5. The choices are
   

• [1:Dim] to change the dimension of a matrix (in fact redefining the matrix)
• [2:Data] enter values in a matrix
• [3:MatA] access Matrix A
• [4:MatB] access Matrix B
• [5:MatC] access matrix C
• [6:MatAns] access the Answer Matrix (the last matrix calculated)
• [7:det] Calculate the determinant of a matrix already defined
• [8:Trn] The transpose of a matrix already defined

Once you have created a square matrix, for example matA.
You press [Shift][Matrix] [7:det] [SHIFT][MATRIX][3:MatA], close the parenthesis and press [ENTER].

If you have defined two similar matrices (same number of row and same number of columns) you can ADD them or subtract them. The operation keys are Plus and Minus as for any number.
To multiply you use the multiplication sign. The matrices must be compatible (mxn) multiplied by (nxk).

Here check the manual:

http://support.casio.com/manualfile.php?rgn=5&cid=004001004

Hello
First you must set Matrix calculation
[MODE][6:Matrix]. Then By entering one of the numbers [1:MatA] or [2:Matb] or [3:MatC] you get to choose the dimensions of the matrix
(mxn]. Once finished entering the matrix you clear the screen.
The operations on matrices are available by pressing [Shift][Matrix]
[1:Dim] to change the dimension of a matrix (in fact redefining the matrix)
[2:Data] enter values in a matrix
[3:MatA] access Matrix A
[4:Matb] access Matrix B
[5:MatC] access matrix C
[6:MatAns] access the Answer Matrix (the last matrix calculated)
[7:det] Calculate the determinant of a matrix already defined
[8:Trn] The transpose of a matrix already defined

To add matrices MatA+MatB
To subtract MatA-MatB
To multiply MatAxMatB
To raise a matrixe to a power 2 [x2], cube [x3]
To obtain inverse of MatA already defined MatA[x-1] [x-1] is the x to the power -1 key
Dimensions of matrices involved in operations must match (see you textbook for the rules)

Read the appendix to your user manual, there are several exemples.
Hope helps