MATLAB: How to solve this matrix using inverse function

inverse

I want to use the inverse function (inv) on this 10 x 10 matrix but I keep getting all this Inf in place of the numbers.
The matrix goes as follows,
 clc,clear all
 a = [1 2 3 4 5 6 7 8 9 10];
b = [21 22 23 24 25 26 27 28 29 30];
c = [11 12 13 14 15 16 17 18 19 20];
d = [31 32 33 34 35 36 37 38 39 40];
f = [41 42 43 44 45 46 47 48 49 50];
g = [61 62 63 64 65 66 67 68 69 70];
h = [51 52 53 54 55 56 57 58 59 60];
i = [81 82 83 84 85 86 87 88 89 90];
j = [91 92 93 94 95 96 97 98 99 100];
e = [1 2 3 4 5 6 7 8 9 10];
 aa = sum(a);
bb = sum(b);
cc = sum(c);
dd = sum(d);
ff = sum(f);
gg = sum(g);
hh = sum(h);
ii = sum(i);
jj = sum(j);
ee = sum(e);
 AA = [a ;b ;c ;d ;e ;f ;g ;h ;i ;j];
b = [aa ;bb ;cc ;dd ;ff ;gg ;hh ;ii ;jj ;ee];
 Res = inv(A)
 The result I am getting is this one,
 Warning: Matrix is singular to working precision. 
> In borrame at 39
 Res =
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf
Why if the command (inv) not working? Please help.

Best Answer

Assuming inv(A) is a typo and you really meant inv(AA):
"a" and "e" are the same, so you have two rows in AA that are the same. This linear dependency creates a singular matrix AA.
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