Question 408508
 I need to lose weight. I figure I can accomplish this by eating less calories per week. By the 4th week I was eating 2700 calories per day. By the 7th week I was eating 2100 calories per day.
You have 2 points relating week and calories: 
(4,2700) and (7,2100)
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a. Let x = week number. Calculate the linear equation that calculates the number of calories per week consumed.
slope = (2100-2700)/(7-4) = -600/3 = -200
Form: y = mx + b
Solve for "b":
2100 = -200*7 + b
2100 = -1400 + b
b = 3500
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Equation:
calories = -200(week) +3500
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b. In which week will I reach my goal of 1500 calories per day?
Solve: 1500 = -200x + 3500
-200x = -1000
x = 5  (in the 5th week)
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Cheers,
Stan H.
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