What is a Linear Function?



The cost of training defense people for certain task increases with respect to the number of people as shown in the following table.

no. of people cost (in $1,000)
1015
2025
3035
4045
5055

Did you notice that the relationship between the cost and the no.of people is a linear one?

In fact, the relationship can be represented by the following linear equation.
cost = 5 + no. of people

Assigning a letter to the function name, we can say that C(n) is the cost of training "n" people, and the equation is
C(n) = 5 + n

Graphing interactive workbench

In general, a linear function is a function defined by an equation of the form

f(x) = y= mx+b

and the graph of a linear equation is a straight line. In the above equation, "m" is called the slope of the line and "b" is called the intercept on y-axis.