how to solve average rate of change x=-1 to x=2

Question

y = f(x) =4x^2-2x

 

Answer 1

f(x) = y = 4x^2-2x

a = -1, b = 2

f(-1) = 4(-1)^2-2(-1)

= 4+2 = 6

f(2) = 4(2)^2-2(2)

= 4*4-4 = 12

Average rate of change = f(b)-f(a)/b-a

= (12-6)/(2-(-1))

= 6/3

= 2

Average rate of change of y = 4x^2-2x is 2.