For a certain value of $k$, the system x + y + 3z &= 10, \\ -4x + 3y + 5z &= 7, \\ kx + z &= 3 has no solutions, what is this value of $k$
+128408 x + y + 3z = 10
-4x + 3y + 5z = 7
kx + z = 3
Multiply the first wquation through by -3 and we have
-3x -3t - 9z = -30 add this to the second equation and we have that
-7x -4z = -22 (4)
Multiply the last equation through by -4 and we get
-4kx - 4z = -12 (5)
Lokking at (4) and (5)..... this will have no solution if
-4k = -7
k = -7/ -4
k =7/4
