Now, let's do the same as we did for the previous one here.

notice again, how did we get 84 for the 4th element's coefficient? well 36 * 7 / 3. and so on. And you can just expand it from there.
Answer:
x=-10 is your answer
Step-by-step explanation:
2(-2x+2)+x+3=37
-4x+4+x+3=37
-4x+4+x=34
-4x+x=30
-3x=30
x=-10
Answer: -2
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Draw a vertical line through 4 on the x axis. This vertical line crosses the parabola at some point (which we'll call point A). Draw a horizontal line from point A to the y axis and note how it lands on y = 12. Therefore the point (4,12) is on this parabola.
Repeat the same steps as before to find that (8,4) is also on the parabola
We need to find the slope of the line through (4,12) and (8,4)
m = (y2 - y1)/(x2 - x1)
m = (4-12)/(8 - 4)
m = -8/4
m = -2
The slope of this line is -2 meaning that the average rate of change from x = 4 to x = 8 is -2.
The line goes down 2 units each time you move to the right 1 unit.