For example, \(y=\frac{4}{x-2}\): Note that as the graph approaches x=2 from the left, the curve drops rapidly towards negative infinity. This is because the numerator is staying at 4, and the denominator is getting close to 0. That means that the fraction itself is getting very big and negative.
Causes of flooding. A flood occurs when a river bursts its banks and the water spills onto the floodplain. Flooding tends to be caused by heavy rain: the faster the rainwater reaches the river channel [river channel: The part of the river that holds the water. ] , the more likely it is to flood.
It can also be caused by heavy snow melt and ice jams. The damage from a river flood can be widespread as the overflow affects smaller rivers downstream, often causing dams and dikes to break and swamp nearby areas. There are two main types of riverine flooding: Overbank flooding occurs when water rises overflows over the edges of a river or stream. This is the most common and can occur in any size channel â from small streams to huge rivers.