How do you solve equations with matrices?

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In summary, solving equations with matrices involves reducing the equation to a simple equation in each entry and rearranging to find the values of the matrices. This process remains the same even if coordinates are involved in the equation.
  • #1
3m0k177y
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How do you solve equations that have matrices?
heres an example (its just off the top of my head)

3x+y=z+4 where
x=1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1
and y=0 0 0 1
0 0 1 0
0 1 0 0
1 0 0 0
and a follow up question; does the process change if coordinates are involved in the equation?
if so, how?
 
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  • #2
Your equation doesn't make any sense. On the left hand side, if x and y are 1x4 matrices then 3x+y is a 1x4 matrix. That's OK. The left hand side is the matrix 3 0 0 4.

So the right hand side must also be a 1x4 matrix, but can't add a matrix to the scalar "4".

I have no idea what you think the array of numbers after the equation means.
 
  • #3
I will answer your question assuming that you meant 4 to be 4*E, where E is the identity matrix of GL(4,R) (i.e x=E).

To solve the system you are given you simply reduce it to a simple equation in each entry. So if we denote by Xij, Yij, Zij, Eij the entry in the ith row, jth column of X,Y,Z,E respectively, the equation becomes:

3Xij+Yij=Zij+4Eij

for every i and every j. Rearrange:

Zij=3Xij+Yij-4Eij

Hence Z is the matrix:

-1 0 0 1
0 -1 1 0
0 1 -1 0
1 0 0 -1

Hope that helps :smile:
 

FAQ: How do you solve equations with matrices?

How do you solve equations with matrices?

To solve equations with matrices, you first need to set up the equation in a matrix form. Then, use the properties of matrices to manipulate the equation and isolate the variable you are solving for. Finally, use inverse operations to solve for the variable.

What are the properties of matrices that can be used to solve equations?

The properties of matrices that can be used to solve equations include scalar multiplication, addition, and multiplication. These properties allow you to manipulate the matrix equation without changing the solution.

Do you need to know how to do row operations to solve equations with matrices?

Yes, row operations are an essential part of solving equations with matrices. They allow you to manipulate the matrix equation and ultimately solve for the variable.

Can you solve any type of equation with matrices?

No, matrices can only be used to solve linear equations. Non-linear equations require different methods of solving, such as graphing or substitution.

How do you know if a matrix equation has a solution?

A matrix equation has a solution if the matrix is consistent, meaning that it has a unique solution or an infinite number of solutions. A consistent matrix has a non-zero determinant, and an inconsistent matrix has a determinant of zero.

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