Question 393682
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Hi
Using the standard slope-intercept form for an equation of a line y = mx + b
  where m is the slope and b the y-intercept.  
7x + 63y = 9     |solving for y to put into the slope-intercept form to find m
 y = -(1/9)x + 1/7   | m = -(1/9)
Lines perpendicular will have a slope m = 9  (the negative reciprocal of -(1/9))