Answer: true
Explanation:
A system of linear equations can be written as:
y = a*x + c
y = d*x + f
Now, the idea of this is find the point (x, y) where both linear equations meet.
Particularlly, if the slope in both equations is the same, we will have two options:
1) The lines are parallel, so they never met, and the system has no solution.
2) The lines are the same lines (this happens when c = f) and this means that we have infinite solutions.
So it is true, if the slopes are the same, the linear system is not consisten.