Answer:
4
Step-by-step explanation:
The average rate of change of f(x) in the closed interval [ a, b ] is
[tex]\frac{f(b)-f(a)}{b-a}[/tex]
Here [ a, b ] = [ 0, 4 ] , thus
f(b) = f(4) = - 4² + 8(4) - 4 = - 16 + 32 - 4 = 12
f(a) = f(0) = - 4 , then
average rate of change = [tex]\frac{12-(-4)}{4-0}[/tex] = [tex]\frac{12+4}{4}[/tex] = [tex]\frac{16}{4}[/tex] = 4
