Let f(x)=x^2+3x-12 what is the average rate of change from x=3 and x=5?

can someone me out and show your work

11

Step-by-step explanation:

The average rate of change of f(x) in the closed interval  [ a, b ] is

here [ a, b ] = [ 3, 5 ]

f(b) = f(5) = 5² + 3(5) - 12 = 25 + 15 - 12 = 28

f(a) = f(3) = 3² + 3(3) - 12 = 9 + 9 - 12 = 6

Hence

average rate of change = = = 11