Question

Can you guys help me with 3-8 please thank you <3

Answer 1

For number 3 The rest are all the same just with different numbers):

$R_{ave}=\frac{f(b)-f(a)}{b-a}$
$R_{ave}=\frac{f(3)-f(1)}{3-1}$
$R_{ave}=\frac{(2(3^{2})-20(3))-(2(1^{2})-20(1))}{2}$
$R_{ave}=\frac{(2(9)-60)-(2(1)-20)}{2}$
$R_{ave}=\frac{(18-60)-(2-20)}{2}$
$R_{ave}=\frac{(-42)-(-18)}{2}$
$R_{ave}=\frac{-24}{2}$
$R_{ave}=-12$