Question 254702
The average rate of change formula is
(i) {{{(f(b)-f(a)) / (a-b)}}}
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For y=x^2, find the average rate of change as 
a) x changes from 1 to 3
using (i) we get
{{{(f(3)-f(1)) / (3-1)}}}
which is
{{{(9-1) / (2)}}}
or
4
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b) x changes from 2 to 5
using (i) we get
{{{(f(5)-f(2)) / (5-2)}}}
which is
{{{(25-4) / (3)}}}
or
7