How do you find a standard form equation for the line with (-2, 2); perpendicular to y = 4?

1 Answer
Jun 13, 2017

When given a line of the form, #ax+by=c#, you can make a perpendicular line by:

Swap "a" and "b": #bx+ay=c#

Make "a" negative: #bx-ay=c#

Set it equal to an unknown constant: #bx-ay=k#

Explanation:

Given: #y = 4" [1]"#

Standard form for equation [1] is:

#0x + y = 4#

To make a perpendicular line:

Swap "a" and "b":

#x+ 0y = 4#

Make "a" negative:

#x- 0y = 4#

Set it equal to and unknown constant:

#x-0y=k#

Use the point #(-2,2)# to find the value of k:

#-2-0(2)=k#

#k = -2#

The standard form is:

#x - 0y=-2#