Answer:
- 1
Step-by-step explanation:
The average rate of change in the closed interval [ a, b ] is
[tex]\frac{f(b)-f(a)}{b-a}[/tex]
Here [ a, b ] = [4, 7 ], thus
f(b) = f(7) = 7² - 4(7) - 1 = 49 - 28 - 1 = 20
f(a) = f(- 4) = (- 4)² - 4(- 4) - 1 = 16 + 16 - 1 = 31
average rate of change = [tex]\frac{20-31}{7+4}[/tex] = [tex]\frac{-11}{11}[/tex] = - 1
