You are here:

Advanced Math/Finding the rule


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?

By graphing, you can see that (6, 54), (10, 50), and (12, 48) lie on the same straight line.

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.

Advanced Math

All Answers

Answers by Expert:

Ask Experts


Janet Yang


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.


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

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

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

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

©2017 All rights reserved.