The row-reduced form of a system of three linear equations in three variables is given by this matrix. How many solutions does the system have?
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Answer:
B. infinite solutions along a line
Step-by-step explanation:
The matrix is equivalent to the equations ...
x = 2
y = 9
0z = 0 . . . . . . true for any z
This tells you the solutions are ...
(x, y, z) = (2, 9, z)
This defines a line parallel to the z-axis.