Solve systems of equations graphically on Octave

If the solutions are assumed to only be integers this can be a brief way to visually solve the equations by looking at the graphs. Note that the complementary case below the y-axis is don't covered here. Here both graphs are plotted on the same axes using the hold on function and is evaluated at integer intervals. Both functions are rearranged to be in terms of x. The mouse can then be used to click the intersections points. Hopefully, this serves as a starting point.

clf;
x = (-5: 1: 5);
y = sqrt(29 - x.^2);
plot(x,y,'.-');
hold on

x = (-5: 1: 5);
y = sqrt(9 + 4*x.^2);
plot(x,y,'.-');