4 linear equations, 5 variables
Designate the equations as $(1),(2),(3),(4)$.
Equation $(3) = (1) - 2*(2)$. So equation $(3)$ is useless.
Equation $(4) = 3*(2) - (1)$. So equation $(4)$ is useless.
By useless I mean it provides no new information.
There are only two linearly independent equations in five variables.