Okay i have a simple problem, and its not working!(adsbygoogle = window.adsbygoogle || []).push({});

I have the following:

Find a 2x2 matrix

A =

-5 3

2 -9

A-1 =

-3/13 -1/13

2/39 -5/39

A*A-1 = I

1 0

0 1

but its saying the inverse i got is wrong! how is this?

det i got was 1/39

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# Homework Help: Why isn't this working? a simple inverse of a 2x2 matrix

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