| 
 
 
 
Question 910816:  Write an equation of the line passing through (4,-2) and perpendicular to x= 5/4 y - 2 
 
 Answer by LinnW(1048)      (Show Source): 
You can  put this solution on YOUR website! x= 5/4 y - 2 
First change the form of the original equation by solving for y 
add 2 to each side 
x + 2 = 5/4y 
reorder 
5/4y = x + 2 
multiply each side by 4/5 
 y = 4/5x + 2(4/5) 
The slope of the original equation is 4/5, 
so the slope of a line perpendicular is -5/4. 
Now we want to use the template y = mx + b and the point (4,-2) 
We have m = -5/4 , x = 4 and y = -2 so y = mx + b becomes 
-2 =(-5/4)(4) + b 
-2 = (-20/4) + b 
-2 = -5 + b 
add 5 to each side 
 3 = b 
Our equation thru point (4,-2) is y = (-5/4)x + 3 
  | 
 
  
 
 |   
 
 |   
 |  |