Question 1115090
What is the equation of the line, in point-slope form, that goes through (2, -1) and is perpendicular to y = 5x + 3?
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Find the slope of y = 5x + 3
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The slope of lines perpendicular to it is the negative inverse of the line's slope.  Call it m.
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Then use y-y1 = m*(x-x1) where (x1,y1) is the point.