Hey Tutu.
Show that when k != 13 then the determinant of the matrix is non-zero and thus has an inverse (which means unique solution).
Have you come across determinants?
Hi a short one, I got everything except this last part.
Show that a unique solution exists for all other k. Find this solution.
I constructed a matrix from the equations
x+2y-2z = 5
x-y+3z =-1
x-7y+k = -k
and found out that there will be infinite no of solutions when k =13
When k is not 13, the system will have a unique solution, but as the question asks, how am I supposed to show? And how do I find the value when they say all other values of k, it doesn't make snese to e because I can't possibly use all values exceept 13..
Thank you very much!