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.
1 Dry soil can produce flooding when very intense rainfall occurs. 2  In the West, most canyons, small streams and dry arroyos are not easily recognizable as a source of danger. 3  A wall of water 10-15 feet high can scour a canyon suddenly. 4  Ice jams and snowmelt can help cause flash floods.