First, you would need to find the slope of those two points by doing change in y over the change in x and you'd get 1-(-9) over -6-5 to get the slope of -11/10. Now you know the slope and have points available to use. Using the point (-6,1) and point-slope formula y-y1=slope(x-x1) you can substitute and get y-1=-11/10(x-(-1))
You got add all the numbers up and divide it by how many numbers there are to get the average. 9.4 +9.7 + 9.9 + 9.8 = 38.8 divided by 4 =9.7 is Joey's average. 9.5 +9.2 +9.7 +9.6 =38 divided by 4 = 9.5 is Carlos' average. Joey has more average by 0.2.
