Question 81490
x + 5y = 10
-2x - 10y = -20

If I look at the equations carefully...
I see that I can get the (2) equation by simply multiplying (1) by -2

These type of equations are called dependent equations, as they will have same solution. If we try to plot a graph for each of the equation.. we will get only one single line.. 
Please visit --  http://www.purplemath.com/modules/systlin2.htm   --  to see and learn more about system of linear equations.


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