Why do we divide the sum of the standard deviation scores by the sample size minus one?

When drawing a trend line for a series of data on a scatter plot, which of the following is true? a. there should be an equal number of data points on either side of the trend line. b. all the data points should lie on one side of the trend line. c. the trend line should not intersect any data point on the plot. d. the trend line must connect each data point on the plot.

Solve the following inequalities and show the solution on a number line. 3/4 (2x-7) ≤ 5

Solving algebraic equations 2m+3=11