SOLUTION: Write the equation of a line that passes through (8,2) and is perpendicular to 4x-y=12

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Question 1021706: Write the equation of a line that passes through (8,2) and is perpendicular to 4x-y=12
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
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From the original equation:
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4x-y=12
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4x=y+12
y=4x-12 (RED LINE on graph)
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The original slope was 4, so the slope of the perpendicular is -1/4.
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y=(-1/4)x+b
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Use the given point to find b (x=8, y=2):
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2=(-1/4)(8)+b
2=-2+b
4=b
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y=mx+b
y=(-1/4)x+4 (GREEN LINE is graph)
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ANSWER: Equation of the perpendicular line is y=(-1/4)x+4
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GRAPH:
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+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+4x-12%2C+%28-1%2F4%29x%2B4%29+
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