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Question 169771:  Write the equation of the line passing through (3,-2), but perpendicular to y=3.
 
I tried to use the point-slope intercept form to find the slope, but I do not have two points given. So I used the first point (3,-2) and (0,3) since y=3. Then I tried to find my slope.
 
y2-y1/x2-x1= 3-(-2)/0-3= -5/3  
now I have a slope of -5/3
 
Next I tried to use the point-slope equation
 
y-y1=m(x-x1) 
y-(-2)=-5/3(x-3) 
y+2=-5/3(x-3) 
3y+6=-3x+9 
3y=-3x+3 
Y=-x+1 
 
Now that I have my equation is this equation perpendicular to y=3?  
Do I have the right concept? 
 Found 2 solutions by  Alan3354, solver91311: Answer by Alan3354(69443)      (Show Source):  Answer by solver91311(24713)      (Show Source): 
You can  put this solution on YOUR website! You made this way too difficult on yourself.
 
 
  is a horizontal line, therefore the desired perpendicular must be a vertical line.  Vertical lines have the characteristic that the x-coordinate for any ordered pair representing a point on the line is a constant value, and the y-coordinate can be any real number.  Hence, if the desired line passes through (3,-2), then the x-coordinate of ALL points on the line must be 3 and therefore the equation of the desired line is   
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