The proper format for this equation y-1/6x+9 is y = (-1/6)x+9.
Any line perpendicular to y = (-1/6)x+9 has the slope which is the negative reciprocal of that of y = (-1/6)x+9, or the negative reciprocal of -1/6. That is +6.
Thus, the desired line, which passes through (6, -3), is found using the point-slope formula for the equation of a straight line:
How To Find Volume of Pyramid With Slant Height? If 'x' is the base length, 's' is the slant height, and 'h' is the height of a regular pyramid, then they satisfy the equation (the Pythagoras theorem) (x/2)2 + h2 = s2.
