B. Functions

A function is often represented as an equation with an input value, x, which will yield an output value, y.

Example 1

Given y = 3x + 15 , solve for y when x = 3.

y = 3x + 15
y = 3(3) + 15
y = 9 + 15
y = 24

y = 24 (output), when x = 3 (input)

In Math 10C, you learned about linear functions. Some of the characteristics you learned about are unique to linear functions. For example, a linear function will generate ordered pairs that, when plotted on a graph, can be connected to produce a straight line.

Functions can be represented in several ways, including mapping diagrams, tables of values, graphs, equations, and written descriptions.

The pairing of input and output values for a particular function is called mapping.

An equation is a way to show a mathematical relationship between variables. In an equation, variables are used to represent the sets of possible numbers with which they could be replaced.