Graph both the algebraic equation and the other equation in question, on an x and y coordinate system.
Count the number of times that the algebraic equation intersects with the other equation.
Set the two equations equal to each other, alternatively. For instance, if you want to determine the number of times x=y intersects with the circle x2+y2=4, substituting the first equation into the second leads to the equation y2+y2=4, or 2y^2=4, simplifying to y=+/- sqrt (2). Simultaneously, x will equal +/- sqrt(2), meaning that there are two possible intersection points.