Question 1159515
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<pre>

Let the rows of the given matrix be  E1,  E2  and E3, counting from the top to the bottom.


Notice that the row  2E1 - E2 is equal to

    [-9,  -2,  -11].


It will be exactly equal to the third row,  E3,  if  -9 = -6+k, i.e. k= -3.


Then the determinant of the matrix will be zero.


<U>ANSWER</U>.  k = -3.
</pre>

Solved.