Question

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

Answer 1

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`