## greeneyes<3 3 years ago Solve the matrix equation.

1. greeneyes<3

[-5, -13_0, 5]X=[3, 1_-4, 0] Sorry idk how to use the other equation sign thing :P

2. greeneyes<3

My teacher that when you multiply you have to do it from the left or you will get a different answer... My answer was X=[1.48, -.8_-.2, 0]

3. greeneyes<3

So it would be multipled [-.2, -0.52_0, 0.2] [3, -4,_1,0]

4. greeneyes<3

is it alright if i multipled from the left instead of the right? that what my book and my teacher did, so i'm confused. idk which way is the right way... :(

5. joemath314159

You are correct. You have to multiply on the left to get the right answer. Matrix multiplication is not commutative, so the order of multiplication is really important.

6. asnaseer

yes greeneyes - you (and joemath) are right. you MUST multiply on the left or you will get the wrong answer. I believe across has the wrong answer here. e.g if: \[AX=B\]then:\[A^{-1}AX=A^{-1}B\]therefore:\[X=A^{-1}B\]

7. greeneyes<3

Thank you both so much! :)

8. asnaseer

yw