What is the biggest city in the world ?

Largest as in population size it's Tokyo,Japan

Master planned communities outside of chicago. note: population density means people living in an area per square mile. chicago, an urban and highly populated area has a much more higher density than a desert, amish community, settlement, or nomadic region.

2. x2 + 8x + 12 = 0 to prove: x = -6 or x = -2