Question 1197570
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Plug in x = 4
A(x) = pi*x^2
A(4) = pi*4^2
A(4) = 16pi


Repeat similar steps for x = 6 to find that A(6) = 36pi


The average rate of change is then:
{{{(A(6)-A(4))/(6-4) = (36pi-16pi)/(6-4) = (20pi)/2 = 10pi}}}


Answer: <font color=red>10pi</font>
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