Any number substituted for y will give a defined value for x, since any number may be squared and multiplied by 4 and an answer given. So y can be any number. Therefore the range is "all real numbers" or Range =Solve for y An even-root radical such as a square root radical cannot caontain a negative number in real mathematics. So what's under the radical must be greater than or equal 0: So which becomes So the domain is To graph, choose x negative or zero so -x will be positive and be square-root-able, x | y ------- 0 | 0 -4 | ±1 -16 | ±2 Edwin