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.
What Causes Flooding? There are many reasons why floods occur, these can be divided into categories of causes. These are flash floods, storm surge, and dam and levee failures. Flash Floods These types of flood occur with little or no warning. Flash floods can be deadly due to the rapid rise in water levels and the high flow-velocities of the water. There are factors which contribute to the occurrence of flash floods: rainfall intensity, duration, surface condition and topography.