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Robert is on a diet to lose weight before his Spring Break trip to the Bahamas. He is losing weight at a rate of 2 pounds per week. After 6 weeks, he weighs 205 pounds. Write and solve a linear equation to model this situation. There should be at least 3 lines of work.

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Answer: Let x be the number of weeks since Robert started his diet, and let y be his weight in pounds. We know that he is losing weight at a rate of 2 pounds per week, so the slope of the line is -2 (negative because he is losing weight). We also know that after 6 weeks, his weight is 205 pounds, so we have the point (6, 205).

Using the point-slope form of a linear equation, we can write the equation of the line as:

y - 205 = -2(x - 6)

Simplifying this equation gives:

y - 205 = -2x + 12

y = -2x + 217

Therefore, the equation that models Robert's weight loss is y = -2x + 217.

To find how much weight Robert will lose after 8 weeks, we substitute x = 8 into the equation:

y = -2(8) + 217

y = 201

Therefore, Robert will weigh 201 pounds after 8 weeks on his diet.

To check that this answer is reasonable, we can use the information that Robert is losing weight at a rate of 2 pounds per week. In 8 weeks, he would have lost:

2 pounds/week x 8 weeks = 16 pounds

205 pounds - 16 pounds = 189 pounds

Since 201 pounds is more than 189 pounds, our answer of 201 pounds after 8 weeks is reasonable.

So the completed work is:

Let x be the number of weeks since Robert started his diet, and let y be his weight in pounds.

We know that he is losing weight at a rate of 2 pounds per week, so the slope of the line is -2 (negative because he is losing weight).

We also know that after 6 weeks, his weight is 205 pounds, so we have the point (6, 205).

Using the point-slope form of a linear equation, we can write the equation of the line as:

y - 205 = -2(x - 6)

Simplifying this equation gives:

y - 205 = -2x + 12

y = -2x + 217

Therefore, the equation that models Robert's weight loss is y = -2x + 217.

To find how much weight Robert will lose after 8 weeks, we substitute x = 8 into the equation:

y = -2(8) + 217

y = 201

Therefore, Robert will weigh 201 pounds after 8 weeks on his diet.

Explanation:

User Akshay Maldhure
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