olve the following system of equations 5x, -6x2 + x3 =-4 - 2x + 7x2 + 3x3 = 21 3x-12x2 - 2x3 = -27 with a) naive Gauss elimination, b) Gauss elimination with partial pivoting, c) Gauss-Jordan without partial pivoting, d) LU decomposition without pivoting. e) Determine the coefficient matrix inverse using LU decomposition in (d). Check your results by verifying that [A[A^-1] = [1]