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Determine if the lines are perpendicular

Determine if the lines are perpendicular-example-1
User DGKarlsson
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1 Answer

6 votes

Answer: Yes, they are perpendicular

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Work Shown:

Find the slope of line A

m = (y2-y1)/(x2-x1)

m = (2-(-2))/(5-(-3))

m = (2+2)/(5+3)

m = 4/8

m = 1/2

The slope of line A is 1/2.

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Repeat for the slope of line B

m = (y2-y1)/(x2-x1)

m = (2-(-6))/(-1-3)

m = (2+6)/(-1-3)

m = 8/(-4)

m = -2

The slope of line B is -2

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Since the second slope is the negative reciprocal of the first slope, this means the two lines are perpendicular.

Put another way: the two slopes (-2 and 1/2) multiply to -1, so the lines are perpendicular.

User Luca Faggianelli
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