Question 417958
-30x - 15y = -30
30x + 15y = 30
---------------
0 = 0
= infinite solutions

 
When the variable disappears and you get a true statement, such as 0 = 0,
then there are "infinite solutions".  This means, the two lines intersect
in an infinite number of points.  In other words, the two equations are equivalent, 
and would create the same line when graphed.


When the variable disappears and you get a false statement, such as 0 = 3,
then thee is "no solution".  This means, the two lines would not intersect.
In other words, the two equations, when graphed, would create parallel lines.
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