Step 1: First of all we require an equation for which we want to calculate the average slope. We will write this equation in form of a function. Assume that equation is f(x) = x2 + 2x – 1.
Step 2: We have a formula for calculating the average slope of a function that is:
A = (f(x) –f(a)) /(x – a),
'A' represents the average slope. Here (x - a) is used to represent the change in input values and f(x) – f(a) is used to denote the change in output of the function f(x).
Step 3: Now we will choose any random values for variables 'x' and 'a'. We have to remember one thing that value we select has a great impact over the outcome value. These points represent the coordinates on graph. For above function we choose the value of x = 3 and a = 0.
Step 4: Now we will place the value of 'x' in the function and calculate the function f(x) and we will place the value of variable 'a' in the function and we will get the value of f(a).
f(x) =32 + 2*3 - 1 = 14,
f(a) = 02 + 2 * 0 -1 = -1.
Step 5: Now put the values of Functions in formula of average slope.
A = (14 – (-1)) / (3 - 0) = 15 / 3 = 5.