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(SAT Prep) Find the value of x in each of the following exercises:

THANKS FOR THE HELP

How to determine whether two known pairs of points are on the same line.

Kelly is a salesperson at a shoe store, where she must sell a pre-set number of pairs of shoes each month. at the end of each work day the number of pairs of shoes that she has left to sell that month is given by the equation s=300-15x , where s is the number of pair of shoes kelly still needs to sell and x is the number of days she has worked that month. what is the meaning of the number 300 in this equation

Give all possible names for the line shown.calculation tip: lines can be written with either point first.