Questions on Algebra: Matrices, determinant, Cramer rule answered by real tutors!

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Question 162528: Find matrix X:
3. [6 5] [4 -2] * X = [18 49] [-20 6]
I'm so confused with this problem. I would love to see the correct steps,and correct answer. I could really use some help with this, Thank you so much for your time!: Find matrix X:
3. [6 5] [4 -2] * X = [18 49] [-20 6]
I'm so confused with this problem. I would love to see the correct steps,and correct answer. I could really use some help with this, Thank you so much for your time!
Answer by Fombitz(1789) About Me  (Show Source):
You can put this solution on YOUR website!
Do you mean like this??
(matrix(2,2,6,5,4,-2))(matrix(2,2,x[1],x[2],x[3],x[4]))=(matrix(2,2,18,49,-20,6))
First find the inverse of your first matrix, which we'll call [A].
[A]=(matrix(2,2,6,5,4,-2))
and the inverse of A called [A]inv.
[A]inv=-(1/32)*(matrix(2,2,-2,-5,-4,6))
and then matrix multiply both sides to solve for [X].
.
.
.
The problem would then look like this,
[A][X]=[B]
[A]inv[A][X]=[A]inv[B]
[I][X]=[A]inv[B]
[X]=[A]inv[B]
.
.
.
So we do the matrix multiplication,
[X]=-(1/32)*(matrix(2,2,-2,-5,-4,6))*(matrix(2,2,18,49,-20,6)))
[X]=(matrix(2,2,-2,4,6,5))