Answer:
7
Step-by-step explanation:
The average rate of change of f(x) in the close interval [ a, b ] is
[tex]\frac{f(b)-f(a)}{b-a}[/tex]
Here [ a, b ] = [2, 5 ]
f(b) = f(5) = 2(5)² - 7(5) = 50 - 35 = 15
f(a) = f(2) = 2(2)² - 7(2) = 8 - 14 = - 6, thus
average rate of change = [tex]\frac{15-(-6)}{5-2}[/tex] = [tex]\frac{21}{3}[/tex] = 7
