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In Mathematics / College | 2025-07-08

Solve the equation for $X$.
$X-3\left[\begin{array}{cc}
2 & -8 \\
-4 & 2
\end{array}\right]=\left[\begin{array}{cc}
4 & -6 \\
2 & -8
\end{array}\right]$

Asked by Rhyder2266

Answer (1)

Add 3 [ 2 ​ − 8 − 4 ​ 2 ​ ] to both sides of the equation.
Compute 3 [ 2 ​ − 8 − 4 ​ 2 ​ ] = [ 6 ​ − 24 − 12 ​ 6 ​ ] .
Compute X = [ 4 ​ − 6 2 ​ − 8 ​ ] + [ 6 ​ − 24 − 12 ​ 6 ​ ] = [ 10 ​ − 30 − 10 ​ − 2 ​ ] .
The solution is [ 10 ​ − 30 − 10 ​ − 2 ​ ] ​ .

Explanation

Understanding the Problem We are given the equation X − 3 [ 2 ​ − 8 − 4 ​ 2 ​ ] = [ 4 ​ − 6 2 ​ − 8 ​ ] and we want to solve for the matrix X .

Isolating X To isolate X , we need to add 3 [ 2 ​ − 8 − 4 ​ 2 ​ ] to both sides of the equation. This gives us


X = [ 4 ​ − 6 2 ​ − 8 ​ ] + 3 [ 2 ​ − 8 − 4 ​ 2 ​ ]

Scalar Multiplication First, let's compute the scalar multiplication:

3 [ 2 ​ − 8 − 4 ​ 2 ​ ] = [ 3 ( 2 ) ​ 3 ( − 8 ) 3 ( − 4 ) ​ 3 ( 2 ) ​ ] = [ 6 ​ − 24 − 12 ​ 6 ​ ]

Matrix Addition Now, we add the two matrices:

X = [ 4 ​ − 6 2 ​ − 8 ​ ] + [ 6 ​ − 24 − 12 ​ 6 ​ ] = [ 4 + 6 ​ − 6 + ( − 24 ) 2 + ( − 12 ) ​ − 8 + 6 ​ ] = [ 10 ​ − 30 − 10 ​ − 2 ​ ]

Final Answer Therefore, the solution for X is:

X = [ 10 ​ − 30 − 10 ​ − 2 ​ ]
Examples
Matrix equations are used in computer graphics to perform transformations on objects. For example, to rotate, scale, or translate an object, a matrix is multiplied by the object's vertices. Solving matrix equations allows us to determine the transformations needed to achieve a desired effect. This is also applicable in robotics, where matrix equations are used to control the movement of robot arms and other mechanical systems.

Answered by GinnyAnswer | 2025-07-08