Question

What is the equation of a line that is perpendicular to −x+3y=9 and passes through the point (−3, 2) ?

Answer 1

Answer

the equation of a line that is perpendicular to −x+3y=9 is y=-3x-7

Step-by-step explanation:

Equation of given line is −x+3y=9

we write the equation in y =mx+b to find slope of given line (m)

−x+3y=9

Add x on both sides

3y = x+ 9

Divide by 3 on both sides

$y=\frac{1}{3} x + 3$

Slope of given line = 1/3

Slope of perpendicular line is the negative reciprocal of slope of given line

Slope of perpendicular line = -3

Perpendicular line passes through point (-3,2) that is (x1,y1)

Now we use point slope equation

y - y1 = m (x-x1)

y - 2 = -3(x-(-3))

y - 2= -3(x+3)

y -2 = -3x -9

Add 2 on both sides

y = -3x - 7