I need help with general form or slope intercept form

Question

Perpendicular to the line -3x + y =12 contains the point (-3,2)

Answer 1

Hi Jonelda!

I would begin by first putting the equation into y=mx+b form by adding 3x to each side of the equation:

-3x+y=12

y=3x+12

For a line to be perpendicular, it's slope (m in the line equation) must be the negative reciprocal of the slope of the other line
Negative Reciprocal of 3 is -(1/3)

So the equation of the perpendicular line is y=-(1/3)x+b where b is the y-intercept. To solve for b, we can substitute x and y in the equation with the given coordinates (-3,2)

y=(-1/3)x+b

2=(-1/3)(-3)+b

2=1+b

b=1

 

So the equation of the perpendicular line which passes through the point (-3,2) is:
y=(-1/3)x+1