Spelling Rules - Animals section of Russian

[opaloma]

Hey I was looking at the spelling rules in the Russian Animals section and was confused. It looks like there might be a misprint as two lines say almost the same thing:

"SPELLING RULES"

Note how plurals of «соба́ка» and «ко́шка» end in И: соба́ки, ко́шки, even though you might expect А to turn into Ы.

There are some restrictions on which consonants are used with which vowels when making word forms. Here are the rules for и, а, у vs. ы, я, ю:

[the following two lines look almost the same]

use only И, not Ы, after к, г, х/ ж, ш, щ, ч

use only А, У after к, г, х/ ж, ш, щ, ч and ц (and never use Я, Ю after them)

[scarcerer]

[they] say almost the same thing

But they don't. They look similar because the 7 letter rule (rule 1 in link) and 8 letter rule (rules 3 & 4) are almost identical (but not quite as the names suggest)
http://www.russianlessons.net/grammar/spelling_rules.php