Question 1016777
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y=total cost; b=flat fee, m=cost per minute; x=number of minutes
. 
y=b+mx
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For x=360 minutes:
$215=b+360m
$215-360m=b
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For x=800 minutes:
$435=b+800m
$435-800m=b
. 
$435-800m=$215-360m
$220=440m
$0.50=m
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Cost per minute m=$0.50
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For x=360:
b=$215-360m
b=$215-360($0.50)
b=$215-$180=$35
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The flat fee b=$35
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ANSWER: Equation is y=$0.50x+$35
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CHECK: Use x=$800; y=$435
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y=$0.50x+$35
$435=$0.50(800)+$35
$435=$400+$35
$435=$435
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