y= -1/3x + 5
If the line is perpendicular, it means the slope is negative reciprocal of 3, which is -1/3.
Equation where b (y-intercept) is unknown:
y= -1/3x + b
Replace x with 3 and y with -2 since the line passes through those points.
-2= -1/3(3) + b
-2= -3 + b
Add 3 to both sides of the equation:
1=b, the y-intercept is 1.
The full equation:
y = -1/3x + 1