how do I write an equation in slope-intercept form for a trend line from a scatterplot?

Answer 1

To write an equation in slope-intercept form for a trend line from a scatterplot, you first need to determine the slope and y-intercept of the line.

The slope (m) can be calculated using the formula:

m = (NΣ(xy) - ΣxΣy) / (NΣ(x^2) - (Σx)^2)

where N is the number of data points, Σxy is the sum of the product of each x and y value, Σx and Σy are the sums of the x and y values, and Σ(x^2) is the sum of the squares of the x values.

The y-intercept (b) can be calculated using the formula:

b = (Σy - mΣx) / N

Once you have calculated the slope and y-intercept, you can write the equation in slope-intercept form (y = mx + b). Simply plug in the values of m and b into the equation to get the final equation for the trend line.