Suppose that it costs $40 to place a classified advertisement in the newspaper, plus $5 for each line. then the cost to place an ad x lines long is given by y dollars, where y equals 5 x plus 40. express as an ordered pair the fact that a 17 line ad costs $125.

Y = 2x + 40
an order pair is expressed as (x, y)
so if x represent lines, and there are 15 lines 
then x = 15
and if y represents dollars, and there are 70 dollars 
then y = 70
which you would plug into (x, y) to get the ordered pair ( 15, 70 )
Now express as an ordered pair the fact that an ad costing $60 is 10 lines long

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