# Write x=(pi)/(4) as an equation in rectangular coordinates, (x, y).

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I'm guessing you mean `theta = pi / 4` , otherwise this equation is already in rectangular coordinates.

To go from polar to rectangular, you want to use the fact that:

`"tan" theta = (y)/(x) `

So: `theta = pi / 4` means that ` "tan" theta = "tan" pi/4 = 1`

So: `(y)/(x)=1`, or `y=x`

You can think about this as the line whose angle with the x-axis is `pi/4` (that is the polar coordinate way to think about it)

Or you can think about this as the line with slope 1 and y-intercept 0 (that is the rectangular coordinate way)