Finding equilibria of coupled differential equations requires solving simultaneous equations. The following are linear equations, where the only possibilities are no solutions, one solution, or a whole line of solutions. For each of the following pairs, solve each equation for y in terms of x, set the two equations for x equal, and solve for x. Check that both equations give the same value for y. Sketch a graph with y on the vertical axis.
-6 + 3y + 3x = 0
-2 - 2y - 6x = 0