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Find the equation of the line through (5,-4) which is perpendicular to the like y= -x/2+2.

User KyelJmD
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1 Answer

21 votes
21 votes

Answer:

y=2x-14

Explanation:

Perpendicular lines have slopes that are opposite reciprocals:

Example: 4 and -1/4 are opposite reciprocals

y = -x/2+2 ==> slope for this equation is -1/2

Now take opposite reciprocal of -1/2

1/(-1/2) * (-1) =

1 * (-2/1) * (-1) =

1 * (-2) * (-1) =

1 * 2 = 2

y=mx+b

-4 = 2(5) + b ==> plug in y=-4, x=5, and m=2 from (5, -4) and a slope of 2

-4 = 10 + b ==> solve for b

-4 - 10 = 10 - 10 + b ==> subtract 10 on both sides to isolate b

b = -14

y=2x+(-14) ==> plugin -14 for b in y=mx+b

y=2x-14

User Kaken Bok
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