Question 536295
The secant line goes through two points on a graph.  Find that line by plugging in those x-values (1 and 2) into the equation.  Each results is the corresponding y.<P>
Then use those coordinates to find the slope of the secant line, which is the rate of change.  Slope = {{{(y[2]-y[1])/(x[2]-x[1])}}}<P>
The issue is your equation is incorrect.  It's a straight line.  Its secant line is itself.  There has to be more to the equation, such as f(x)= 3x^2+x.
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