For solving 2x-y = -1 for x and y, another equation in x and y is needed to work out a particular solution.

Stand alone, the equation will have infinite number of solutions represented by y= 2x+1,

for all real values of x. For each value of x, y will have a corresponding real value. All such pairs of x and y values would represent points on the line..

The graph of this line would be as shown below:

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