SOLUTION: The line passing through (x,4) and (4,-5) is perpendicular to a line with a slope of -7/3. What is the value of x?

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Question 390729: The line passing through (x,4) and (4,-5) is perpendicular to a line with a slope of -7/3. What is the value of x?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
The line passing through (x,4) and (4,-5) is perpendicular to a line with a slope of -7/3.
What is the value of x?
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Find the slope of the line perpendicular to slope of -7/3 using: m1*m2 = -1
Let m1 = -7/3, find m2
-7%2F3*m2 = -1
m2 = -3%2F7*-1
m2 = 3%2F7
:
Use the slope formula %28y2-y1%29%2F%28x2-x1%29 = m2
Using the given values
%28-5-4%29%2F%284-x%29 = 3%2F7
:
%28-9%29%2F%284-x%29 = 3%2F7
Cross multiply
3(4-x) = -9*7
12 - 3x = -63
-3x = -63 - 12
-3x = -75
x = %28-75%29%2F%28-3%29
x = +25
:
:
Check this by finding the slope using x=25
%28-5-4%29%2F%284-25%29 =
%28-9%29%2F%28-21%29 = 3%2F7