Fix logical error in scaling code

[unode]

When teaching this section the result was unexpected.
I believe there is a bug in the logic of the code that went undetected so far.

Inverting the scaling factor "fixed the issue" and made the code easier to understand for learners.

[github-actions]

Thank you!

Thank you for your pull request 😃

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Rendered Changes

🔍 Inspect the changes: https://github.com/swcarpentry/python-novice-inflammation/compare/md-outputs..md-outputs-PR-1096

The following changes were observed in the rendered markdown documents:

 10-defensive.md | 2 +-
 md5sum.txt      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

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⏱️ Updated at 2025-02-27 10:03:04 +0000

[ineelhere]

Thank you for the suggestion. Please join the conversation at #1085 for more context on upcoming changes discussed on this same part of the lesson and better collaboration and contributions. If this is not a potential conflict to PR #1085, PR #1096 can be merged to lesson material.

Adding some more context for reference -

The issue occurs when the rectangle is wider than it is tall. This fix ensures the aspect ratio is preserved by scaling dy relative to dx when dx > dy. The original code mistakenly used dx/dy, which inverted the proportions. Now, the longest side is always 1.0, and the shorter side is correctly scaled as dy/dx when needed.

[tmorrell]

This is an intended error in the code to trigger the assertion, which is explained in

python-novice-inflammation/episodes/10-defensive.md

Line 220 in dcb33be

we realize that line 14 should divide `dy` by `dx` rather than `dx` by `dy`.

. Changing this would break the rest of the lesson.