Find equation of the line that is perpendicular

Find the equation of the line perpendicular to y = 4x - 5 and passing through (1,-5) .
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Perpendicular lines have slopes which are negative reciprocals. 

Slope-intercept form is y = mx + b
m is the slope
b is the y-intercept 

In y = 4x - 5,
slope is 4
perpendicular slope is -1/4 

point is (1,-5) , slope is -1/4
y = mx + b   {slope-intercept form}
-5 = (-1/4)(1) + b   {substituted point (x,y) and slope into slope-intercept form}
-5 = (-1/4) + b   {multiplied}
b = -19/4   {added 1/4 to each side} 

y = mx + b   {slope-intercept form}
y = (-1/4)x - (19/4)   {substituted slope and y-intercept into slope-intercept form}

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