Question

What is your equation? Re-watch thelast section if you're not sure how todo it.1 2 3 4 5 6 7 8 9 10Years Since 1998Note: Your equation doesn't have to beperfect ... just give it your best effortand then watch the explanation thatfollows.

Answer 1

Part a.

We are asked to type an equation that could represent the line of best fit shown in the following image:

So, we need just two points on the line that can be used to find the slope and finally the complete equation of the line.

We select two particular points: (1, 61) and (8, 71) whcu seem to be two points where the line goes through.

Then we use the formula for the slope of a line through two points on the plane:

slope = (y2 - y1) / (x2 - x1)

in our case: (71 - 61) / (8 - 1) = 10 / 7

Then the slope-intercept form ofthe equation should look like:

y = 10/7 x + b

we can determine "b" by using one of the points (for example (1, 61)):

61 = (10/7) (1) + b

61 - (10/7) = b

b = 417/7

The final form of the equation is:

y = 10/7 x + 417/7

In approximate decimal form it becomas:

y = 1.43 x + 59.8

Part b:

Interpretation of the slope and y-intercept:

The slope represents the change in percent of graduates per year. so every year there is an increase of about 1.43 % of graduates relative to the previous year.

The y-intercept represents the graduation rate (about 59.8%) when this study started (year 0 zero corresponding to 1998)

Part c:

In order to estimate the prediction of percent of graduates in the year 2020, we first calculate the number of years between 2020 and 1998:

2020 - 1998 =