SOLUTION: Find the value of x so that the line containing (4,8) and (2,-1) is perpendicular to the line containing (x,2) and (-4,5). Graph the lines.
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-> SOLUTION: Find the value of x so that the line containing (4,8) and (2,-1) is perpendicular to the line containing (x,2) and (-4,5). Graph the lines.
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Question 656643: Find the value of x so that the line containing (4,8) and (2,-1) is perpendicular to the line containing (x,2) and (-4,5). Graph the lines. Answer by solver91311(24713) (Show Source):
Perpendicular lines have slopes that are negative reciprocals. Start with the slope formula for the first two points:
Then the slope for the 2nd set of points:
Take the negative reciprocal of
Then set
Solve for . Be very careful with your signs. Particularly the one in front of the RHS fraction. Apply it to either the numerator or the denominator as suits your fancy, but distribute it across BOTH terms of whichever you choose.
John
My calculator said it, I believe it, that settles it
