The line of best fit drawn on the plot shown is used to predict the number of tickets sold on a certain day. Use the two points shown on the line of best fit to calculate its slope to the nearest tenth.
The two most identifiable points are ( 1, 30) and ( 7, 55 )
[ subtract the y coordinates in some order ] / [ subtract the x coordinates in the same order ]
[ 55 - 30 ] / [ 7 - 1 ] =
25 / 6 ≈ 4.2