Arecord label company recently released two albums. both albums are available for purchase as cds or digital downloads. the table shows the number of copies in each format sold on the day of release

In this item, we are given the equations of the lines which serves as the bases of the trapezoid. We are asked to determine the equation of the midsegment. 

The midsegment is also parallel to the bases and that the lines can only be parallel if and only if there slopes are equal. The equations given above has the form,
                    y = mx + b 
where m is the slope and b is the y-intercept. Thus, the slope is equal to -1/4. Also, the y-intercept of the midsegment will be the average of those from the bases. 
                     y-intercept = (5 - 1) / 2 = 2

Hence, the equation of the midsegment is,
              y = -1/4x + 2