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Question
Hello
I am a fifth grader and can not find the rule for
X= 6,10,12,15 and then a blank.  With Y=54, 50,48 then a blank and then 0?
Thanks

Answer
By graphing, you can see that (6, 54), (10, 50), and (12, 48) lie on the same straight line.
http://www.flickr.com/photos/dwread/8559214205/

Use (6, 54) and (10, 50) to determine the slope.
rise = 50 - 54 = -4
run = 10 - 6 = 4
slope = rise/run = -1

Use (10, 50) to write the point-slope equation of the line.
y - 50 = (-1)(x - 10)
Rearrange to solve for y:
y = -x + 60

When x = 15, y = 45.
When y = 0, x = 60.

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Janet Yang

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I can answer questions in Algebra, Basic Math, Calculus, Differential Equations, Geometry, Number Theory, and Word Problems. I would not feel comfortable answering questions in Probability and Statistics or Topology because I have not studied these in depth.

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I tutor students (fifth through twelfth grades) and am a Top Contributor on Yahoo!Answers with over 24,000 math solutions.

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Co-author of An Outline of Scientific Writing: For Researchers With English as a Foreign Language

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I have a Bachelor's degree in Applied Mathematics from the University of California at Berkeley.

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George White Elementary School. Homework Help program at the Ridgewood Public Library, Ridgewood, NJ. Individual students.

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