I'm having difficulty finding the average velocity for f(x) = x² + x

and x goes from 2 to 6

I tried 6-2= 4 and plugging in 4 in my formula but i'm not sure that my average velocity of 20 is right.

Suppose an object moves along the y axis so that its location is y = x} = 12 + x at time x [y is in meters, 1 is in seconds}. Find [A] The average velocity [the average rate of change of y with respect to x} for x changing from 2 to 61 [B] The average velocity for x changing from 2 to 2 + h. {C} The instantaneous velocity at x = 2 second. [A] The average velocity is I] Ween