Question 821391
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given:
f(x) = (-1/7)x + 8
(5,9)
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perpendicular lines have negative reciprocal slopes.
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therefore, the slope of the perpendicular line = 7
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to solve the linear equation, copy and paste this (the given point and the perpendicular slope):
5,9,7
into the "Point-Slope form: x1 y1 m" input box here: https://sooeet.com/math/linear-equation-solver.php
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y-intercept = -26
slope = 7
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answer:
slope-intercept form: 
y = 7x - 26
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