4. Given the system of equations 2x2 + 5x3 = 1 2x1+x2+ x3=1 3x1 + x2 = 2 (a) Compute the determinant. (b) Use Cramers rule to solve for the xs. (c) Use Gauss elimination with partial pivoting to solve for the xs. As part of the computation, calculate the determinant in order to verify the value computed in (a) (d) Substitute your results back into the original equations to check your solution.