What is the slope of a line perpendicular to the line whose equation is 4 x − 2 y = 20 . Fully simplify your answer.

Question

What is the slope of a line perpendicular to the line whose equation is 4x−2y=20 Fully simplify your answer.

Answer 1

Perpendicular lines have opposite, reciprocal slopes, like -1/2 and 2 or 4/5 and -5/4.

4x - 2y = 20

-2y = -4x + 20

y = 2x - 10

y = mx + b and m is our slope. As mentioned above, the opposite reciprocal of 2 is -1/2.

Answer 2

Hi Si P.

It would be useful to put your given line into Slope Intercept form by solving for y

You want it to be in this format

y = mx + b

where m is the slope

First lets list your equation

4x -2y =20

Start solving it for y, by subtracting 4x from both sides of the equation

-2y= -4x + 20

Divide both sides by negative 2

y = 2x - 10

Now your given line is in Slope Intercept form, y = mx + b

m=2

The slope of the perpendicular line is the inverse of 2 with the opposite sign

that would be -1/2

m = -1/2 is the slope of the perpendicular line.

I hope this helps.