Inverse and Matrix Multiplication

Just attempting to solve a few matrices but do not seem to be getting the answer right! Probably easy but im struggling. Also, I'm sorry, I couldnt figure out how to code a matrix into the format so it looks weird.

For this problem, I am attempting to find MX when:

**MX= (Inverse of X x X) x M**

X=

1 2 3

1 1 -1

2 4 7

First, find **X^-1 (Inverse of X) **

Next, find M if **MX**=

-13 -5 17 -13 38

11 -6 6 -24 -5

-32 -7 35 -21 86

Once again, sorry about the formatting of the matrices. hopefully someone can help me out because I think I'm stuffing up the inverse step.