By using the provided A ' find x, from this system of linear equations: 2x1 + 3x2 - 12x3 - 7x4 = 12 -8x2 + -2x4 = 9 X1 + 5x2 - 1X3 = -7 -3x, + 4x2 -9X3 - 2x4 = 1 3 -12 The inverse of the matrix of coefficients, A = 8 0 -2 is given by 4 66 -173 -270 -581 A 1 = 24 64 108 20 36 -54 147 234 42 96 -274 -432 -801 4 8 No need to compute the rest of A-inverse. Find the third column of A where A = 2 4 3 -2 .3 The syntax for entering a single column is Vector([a, b, c]). Give exact values (use fractions if exact decimal is not possible)