Given the function graphed below, what is the average rate of change between f(3) and f(7)?

choice D) 20



Explanation:

Locate 3 on the x axis number line. Draw a vertical line through 3 and this vertical line will cross the parabola at some point P. Mark this point P on the parabola. Then draw a horizontal line from P to the y axis. The horizontal line will land on y = 10. In short, this all shows us that (3,10) is a point on this parabola.

Repeat those steps above, but now for x = 7. You'll see that (7,90) is another point on this parabola.

We need to find the slope of the line through the two points (3,10) and (7,90). The average rate of change from x = 3 to x = 7 is the same as the slope of the line through those two points.

To find the slope, we use the slope formula
m = (y2 - y1)/(x2 - x1)
where (x1,y1) and (x2,y2) are the two points, and m is the slope

In this case,
(x1,y1) = (3,10) and (x2,y2) = (7,90)
further breaking down to
x1=3
y1=10
x2=7
y2=90
So we'll plug those four pieces of info into the equation and simplifying to get...
m = (y2 - y1)/(x2 - x1)
m = (90 - 10)/(7 - 3)
m = 80/4
m = 20

The slope of the line is 20, so therefore, the average rate of change is 20.

Ok here we go ..there are plenty of ways to solve such math problems but we will go for the smartest and easiest ..5x+2y=7  -2x+6y=9we rearrange them into the following ..by multiplying the 1st equation by 2 it becomes 10x + 4y = 14we rearrange it and so it becomes 10x = 14 - 4yas for the second equation we multiply it by 5 and rearrange it so it becomes as to the following ..-10x + 30y = 45rearranging so 10x = 30y -45now 10x equals both 14 - 4y and 30y -45so   14 - 4y = 30y -4531 = 26yy= 31/26 = 1.19 or around 1.2so by now we can calculate x easily as  -2x+6y=9so 2x = 6y -9 = 6 * 31/26 - 9 = -1.84  then x = - 0.92 or around -0.9best luck!