Question 684930
Starting with x - 3y = 9
find the slope
3y = x - 9
y = {{{(1/3)x - 3}}}
slope is {{{1/3}}}
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A perpendicular line will have a negative inverse/reciprocal slope of {{{-3}}}
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Use the slope and the point (4, 1) in the point-slope formula
y - 1 = -3(x-4)
y - 1 = -3x + 12
{{{highlight_green(y = -3x + 13)}}}
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