The line perpendicular to y=1/4x+6 through (1,-6)

D

Step-by-step explanation:

The slope of the perpendicular line is the original line's negative reciprocal. The slope of the line is (since the line is already in slope-intercept form).

The negative reciprocal of is –4. From that alone, we can narrow it down to Choice D, because it is the only line with a slope of –4.

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

step-by-step explanation:

points a and b are equidistant from the desired line, so the line you find by using them will go through point r.

using points other than a and b will give the desired line only if they are equidistant from r. if they are randomly located, the perpendicular line you create will not necessarily go through point r, hence will not be a solution to the problem.