1. The problem statement, all variables and given/known data FP1 (MEI June 07) 2. Relevant equations 3. The attempt at a solution (i) Find the value of n I multiplied the top row of A by the left column of B and got the equation: -5-16+k=k-n moved stuff around and ended up with n=21 (ii)Write down the inverse matrix A-1 and write down the conditions on k for this to exist. Well, I know that k can not be 21 otherwise the determinant will be 0 which cannot be true in this circumstance. I'm not too sure how to do A-1. I know that the matrix itself must be what B originally was, but I'm not sure how to find out what k is (and thus the determinant). (iii)Using the result from part (ii), or otherwise, solve the following simultaneous equations. x-2y+z=1 2x+2y+z=12 3x+2y-z=3 I solved this using Gaussian elimination. I know how to solve this using the inverse of matrices, but I couldn't quite do part (ii) so i was unable to use that method.