Let's start with some definitions. First, a sistem of linear equations means that each equation of the system can be graphed as a line and can be written as follows:
The solutions of a system of linear equations is the interception of the lines of each equation.
If the system is consistent, it means that it has at least one solution.
If the system is dependent, it means that it has infinite solutions.
Graphically, the system has no solution if the lines are parallel (they have the same slope) and they don't itnercept each other, so they have different y-intercepts.
The system will have only one solution when the lines have different slopes.
And the system will have infinite solutions if the lines have the same slope and the same y-intercept, meaning they are the same.
So, a consistent dependent system of linear equations have infinite solutions by definition, meaning the lines are the same, which can be represented graphically by two lines that are together:
In the graph above, we can see an example of this, where the lines are together.