1. The problem statement, all variables and given/known data detA = 0 Matrix A = | (x+5) 4 4 | | -4 (x-3) -4 | | -4 -4 (x-3)| 3. The attempt at a solution I know that if one row or column is equal to another, then detA = 0, so using the last 2 rows, i can find out that x has to be -1 for row2 and row3 to be equal for detA = 0. but the answer at the back says x = -1 or 3, how can i solve the 3? I have tried to reduce it to the triangular form, but it got way too messy to be correct. I also tried using the 3x3 matrix trick where you copy the first 2 rows and make a 4th and 5th row out of them and solve for the determinant, also got pretty messy. Is there some rule that i missed out that can make my life easier on solving this question?