SOLUTION: Find the equation of the line that passes through (3,-5) and is perpendicular to the line that passes through (7,-5) and (-2,-4)

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Question 64698This question is from textbook An Incremental Development
: Find the equation of the line that passes through (3,-5) and is perpendicular to the line that passes through (7,-5) and (-2,-4) This question is from textbook An Incremental Development

Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
FIRST WE FIND THE SLOPE OF THE LINE THROUGH THE 2 POINTS THUS
(Y2-Y1)/(X2-X1)
(-4+5)/(-2-7)
1/-9 IS THE SLOPE OF THE LINE THROUGH ((7,-5)(-2,-4)
NOW TO IDENTIFY A LINE PERPENDICULAR TO THIS LINE IT HAS TO HAVE A SLOPE OF A NEGATIVE RECIPRICAL OF THIS SLOPE. THUS THE SL;OPE OF A LINE PERPENDICULAR TO THIS LINE THROUGH (3,-5) HAS A SLOPE OF 9. NOW WE SUBSTITUTE THESE X&Y POINTS IN THE FORMULA USING THE NEW SLOPE WE GET
-5=9*3+b
-5=27+b
b=-5-27
b=-32 THUS THUIS EQUATION IS
Y=9X-32