Y = (-1/9).x + 4 The slope m of the line perpendicular to y = (-1/9).x + 4 is equal to 9: (if the product of 2 slopes = - 1, then the 2 lines are perpendicular)
y = 9x + b, Since it passes by the point (-1,0) , then: 0= 9(-1) + b and b = 9 Final equation:
12ft = 4 posts 4 x 4 =16 - 4 = 12 There is 4 post on each side but there is an overlap so you must take off 4 so there is no overlap Therefore there are 12 posts
