Answer:
C.
Explanation:
We need to write an equation in slope intercept form.
x - 3y = 12
- 3y = - x + 12
y = 1/3 x + 12
Slope = 1/3, so for perpendicular line slope should be -3.
A. x+ 3y = 9
3y = -x + 9
y = -1/3 + 3 slope = - 1/3
B. 3x - y = 5
y = 3x - 5, slope = 3
C. 3x + y = 6
y = -3x + 6 , slope = -3
D. x - 3y = -3
- 3y = - x - 3
y = 1/3 x + 1, slope = 1/3