X-12 divided by 6=9

how do i do this? two things are being done to x and i don't know which to do first.

Ellen makes and sells bookmarks. she graphs the number of bookmarks sold compared to the total money earned. why is the rate of change for the function graphed to the left?

Susie wants to take her friend out for lunch.she wants to spend $9.75 each person. how much will she spend in all.

Type the correct answer in the box. use numerals instead of words. if necessary, use / for the fraction bar.a city water tank holds 20 gallons of water. a technician empties 25% of the tank. how many more gallons of water must be removed from thetank so that it has 5 of the water that it started with: the technician must removemore gallons of water for the tank to have 5 of the water that it started with.