But assessing for planarity amid the addition and removal of edges is difficult without drawing the graph yourself and trying not to cross any lines (See “The Three Utilities Problem” below ...

Negative four is less than or equal to x, less than or equal to two., Draw the graph of the quadratic equation 𝒚 = 𝒙² + 2𝒙 – 3 for values of 𝒙 from -4 to 2.