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Line p passes through points (5,−3) and (−2, 5) . What is the slope of a line perpendicular to p ?

User Brian Winant
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1 Answer

22 votes
22 votes

Answer:


\displaystyle (7)/(8)

Explanation:

Hi there!

First, find the slope of Line p:


\displaystyle m=(y_2-y_1)/(x_2-x_1) where two points that fall on the line are
(x_1,y_1) and
(x_2,y_2)

Plug in the given points (5,−3) and (−2, 5):


\displaystyle m=(-3-5)/(5-(-2))\\\\\displaystyle m=(-3-5)/(5+2)\\\\\displaystyle m=(-8)/(7)

Therefore, the slope of Line p is
\displaystyle- (8)/(7).

Perpendicular lines always have slopes that are negative reciprocals, such as 1/2 and -1/2, and 3/4 and -4/3.

Knowing this, the slope of a line perpendicular to Line p would be the negative reciprocal of
\displaystyle- (8)/(7), which is
\displaystyle (7)/(8).

I hope this helps!

User Samarth Bhargava
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3.0k points