Question 165171:  Find the equation of the line perpendicular to 3x – 4y = 9 and passing through (-2, -1). Write the equation in standard form, with all integer coefficients.
 
 
 Answer by Alan3354(69443)      (Show Source): 
You can  put this solution on YOUR website! Find the equation of the line perpendicular to 3x – 4y = 9 and passing through (-2, -1). Write the equation in standard form, with all integer coefficients.  
---------------------------- 
1st find the slope of 3x – 4y = 9 
Put it into slope-intercept form y = mx + b 
3x – 4y = 9 
-4y = -3x+9 
y = (3/4)x - 9/4 
The slope, m, is 3/4.  The slope of a line perpendicular is the negative inverse, -4/3. 
------------- 
Use the slope-intercept eqn: 
y-y1 = m(x-x1)  where (x1,y1) is the point (-2,-1) 
y+1 = (-4/3)*(x+2) 
3y+3 = -4x - 8 
4x + 3y = -11
 
 
 
  | 
 
  
 
 |   
 
 |