SOLUTION: The line joining (-5, 7) and (0, -2) is perpendicular to the line joining -(1, -3) and (4, x). find x

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Question 1172314: The line joining (-5, 7) and (0, -2) is perpendicular to the line joining -(1, -3) and (4, x). find x
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
slopes of perpendicular lines multiplied together=-1.
the first slope is -9/5
the second line is -(1, 3). This is an unusual way to write an ordered pair, and I will edit it to mean (-1, -3). Its slope is (x+3)/5 and has to be 5/9
so (x+3)/5=5/9
-
therefore, -(9/5)*(x+3)/5=-1; (9x+27)=25, multiplying first by -1 and then by 25
9x=-2
x=-2/9
Check using point slope formula where y-y1=m(x-x1) m slope (x1, y1) point
for line 1 it is y+2=-(9/5)x or y=-(9/5)x-2.
The second line has points (-1, -3) and (4, -2/9)
its slope is 25/9/5, or 25/45, or 5/9.
y+(2/9)=(5/9)(x-4)
y=(5/9)x-(22/9)
x= -2/9
graph%28300%2C300%2C-5%2C5%2C-5%2C5%2C-%289%2F5%29x-2%2C%285%2F9%29x-%2822%2F9%29%29