If a system of linear equations in two variables has two graphs that coincide, how many solutions are there to the system?

one

infinitely many

none

If a system of linear equations in two variables has two graphs that are parallel lines, how many solutions are there to the system?

How many solutions does a system of equations have if the graphs of the equations are:

Consider what you know about systems of linear equations.

Form and use pairs of simultaneous equations, one of which may be non-linear

Apply systems of equations in solving problems