Question 1152945
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A telephone calling card charges a connection fee,plus a charge per minute. A 5-minute call cost $2.98. A 15-minute call costs $7.18. What is the cost of the connection fee?
2, find the solution:
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y=mx+b
Points as (x,y)
b, connection fee
m, the per minute price


points given are (5,2.98) and (15,7.18).


You could use  b=y-mx, pick either of the given points for x and y, and use {{{m=(7.18-2.98)/(15-5)}}}.

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