Question 1157349
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If a customer uses 420 minutes, the monthly cost will be $64. If the customer uses 910 minutes, the monthly cost will be $113.
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x minutes
y monthly cost


points (x,y) are (420,64) and (910,113).

{{{y=((113-64)/(910-420))(x-420)+64}}}--------------simplify and put into y=mx+b form.