Which of the following choices is the common difference between the terms of this arithmetic sequence?
3x + 7y, 8x + 4y, 13x + y, 18x - 2y, 23x - 5y,

Using elimination, what is -4x+2y=-12 4x+8y=-24

Find the volume of the solid obtained by rotating the region enclosed by the curves y=1x and y=7^-x about the x-axis. (use symbolic notation and fractions where needed.) volume =

A6 ounce bottle of dressing costs $1.56 a 14 ounce bottle costs $3.36 a 20 ounce bottle costs $5.60 which has the lowest cost per ounce