Answer: Choice A) 180
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Work Shown:
f(x) = 3^x
a = 2 = lower value of the interval
b = 6 = upper value of the interval
c = average rate of change of f(x) from a to b
c = ( f(b) - f(a) )/(b - a) ..... note how this mimics the slope formula
c = ( f(6) - f(2) )/(6 - 2)
c = ( 3^6 - 3^2 )/4
c = ( 729 - 9 )/4
c = 720/4
c = 180
The average rate of change from x = 2 to x = 6 for f(x) = 3^x is 180