Question

Using complete sentences, explain how to find the average rate of change for f(x) from x = 4 to x = 7.

Answer 1

so the average rate of change between two points of a function is the slope between the two points.
Remember slope is:
ΔyΔx

(change in y over change in x)
which can be written as:
y2−y1x2−x1

in this case:
x2=7

and
x1=4

To find the y-coordinates plug in the x values into f(x) so:
y2=2(7−9)2+1

y1=2(4−9)2+1

Now just simplify those and plug them into the slope formula to find the average rate of change.

Answer 2

the +1 should be +17

Answer 3

ok thank you so much. did you mean the +1 should be 7?

Answer 4

yesh : P

Answer 5

oh ok thank you. you where a big help and i noticed you changed your picture (;

Answer 6

Yes thanks for noticing : )