The Japanese language sometimes borrows symbols from Mandarin so you both are correct.

Kanji in Japanese looks exactly like Chinese. Kanji is Chinese characters used in Japanese. Hiragana and katakana are the different ones. I guess OP only wrote in kanji. Or the teacher doesn't know much Chinese like me even though we are Chinese.

Ummm, if you were in Algebra when you took out your notebook, how was your Chinese teacher able to comment???? Are they one and the same???

If they are Kanji then she could actually be legit. The Japanese alphabet Kanji means "Chinese letter" and some Kanjis overlap between Japanese and Chinese.

actually japanese context ran out of symbols so they borrowed some chinese symbols

Obviously a chinese-american with no background in her own culture

Those characters could have been kanji…

The Chinese and Japanese share an alphabet. The Japanese have three in all.

The Chinese writing system and the Japanese are the same so where ever you are in Asia you'll still be able to understand the written language even if the spoken language is different.

Well that's not so bad cause it's a good thing if your teacher likes you