MHB How to graph complex number fractions

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When graphing the complex number (3+4i)/25 on a complex plane, the x-coordinate is 3/25 and the y-coordinate is 4/25, not 4i/25. The real numbers are plotted on the x-axis and the imaginary numbers on the y-axis. To locate the point, draw a vertical line at 3/25 on the x-axis and a horizontal line at 4/25 on the y-axis. The intersection of these lines represents the complex number. The correct terminology is to refer to these as coordinates rather than points.
Raerin
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If I'm graphing (3+4i)/25, would the x-point be 3/25 and the y-point be 4i/25?
 
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Raerin said:
If I'm graphing (3+4i)/25, would the x-point be 3/25 and the y-point be 4i/25?

Hi Raerin, :)

If you are marking the complex number \(\frac{3}{25}+i\frac{4}{25}\) on a complex plane you will have your real numbers on the x-axis and your imaginary numbers on your y-axis. First you will have to find \(\frac{3}{25}\) on the x-axis, draw a vertical line through that point. Then find \(\frac{4}{25}\) on the y-axis and draw a horizontal line through that point. The point where these two lines intersect would represent the complex number \(\frac{3}{25}+i \frac{4}{25}\).
 
Raerin said:
If I'm graphing (3+4i)/25, would the x-point be 3/25 and the y-point be 4i/25?
No quite but almost. You are just saying it wrong. It not "x point" and "y point" but "x coordinate" and "y coordinate" of the single point representing the complex number.

The x coordinate is 3/25 and the y coordinate is 4/25 (NOT "4i/25": numbers on the graph, being distances on a line, are real, not imaginary).

In general, the point representing a+ bi is (a, b), with x coordinate a and y coordinate b.
 
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