The solution to a system of (linear) equations is the point where the graphs intersect. Consider two parallel lines. By definition, two parallel lines never intersect each other, but all pairs of non-parallel lines will eventually intersect. That means they will also have a solution.
Let's consider what makes a line parallel to another line. It basically looks identical, having the same steepness (slope), but the graph is just shifted over. That is, a parallel line would have the same slope and a different y-intercept. For our equation

, or

in slope-intercept form, a parallel line will be of the form

.
That describes the form of a parallel line, which we do not want. Any other line, however, will give a solution to our system, so we merely want a line where the slope does not equal 2.
We can have any equation of the form

.
Answer:
C
Step-by-step explanation:
the factor of x in the equation is the slope, which is the ratio y/x indicating how many units y changes, when x changes a certain amount of units.
going from the left point to the right point x changes by +3 units, and y changes by -1 unit.
so, the slope (and factor of x in the equation) is -1/3.
and the constant term in the equation is the y (axis) intercept of the line.
this is the y value, when x = 0 (intercepting the y axis).
and we see in the graph, when x = 0, the line goes through y = 2.
so, the equation has to be
y = -1/3 × x + 2
therefore, C is the right answer.
Three planes a distinct lines have in common
Answer:
what slope and graph? sorry!