| 
 
 
| Question 788853:  How to you solve using linear models? For example, I do not understand to set up an equation. My math teacher said get to points then find your slope, plug it into point-slope form, then plug in your x to find your unknown y. For example this is one of the questions. There are 55 blades of grass in 1 inch of the lawn. There are 230 blades of grass in 4 inches of the same lwn. How many blades of grass are in 3 inches of the lawn?
 Answer by josgarithmetic(39630)
      (Show Source): 
You can put this solution on YOUR website! EDIT: See SECOND ATTEMPT... also, for more condensed, verified, and with Point-Slope form. 
 This can give points, (x, y), and may choose x for inches of lawn, y for blades of grass.
 
 Using that format, you assign points, (1,55) and (4,230).  A linear equation for these two points can be modeled with y=mx+b, where m is slope and b is y-intercept.
 
 
   
 Find b using y-mx=b or b=y-mx for which you pick either point.  Let me use (1,55).
 
  
  
  
  ----( Now Corrected ) 
   
 The linear equation which models this blades of grass description is
  . Give careful attention to how the variables were assigned.  Your question was, how many blades of grass, y, are in 3 inches of lawn, x.  This means, what is y when x=3?
 
 
  (Now Corrected)
 
 ______________________________________________________________
 SECOND ATTEMPT TO BE SURE
 Identifying (x,y) points as Inches of Lawn, Blades of Grass:
 (1,55) and (4,230)
 
 Slope
   
 Use Point-Slope form and use (1,55):
 
   
 Find y when x=3, meaning when Inches of Lawn is 3:
 
  
  
  
  Either
  OR  blades of grass
 | 
  
 | 
 |