Hi Peace IG,

Thanks for sharing this! I took a look at the video in question and the expression in the video seems to be pretty consistent with the notation used in other courses.

For example, if you take a look at some of the videos in the Multiplying Negative Numbers topic, you can see several expressions multiplying two negative numbers without parentheses being used: https://www.khanacademy.org/math/cc-seventh-grade-math/cc-7th-negative-numbers-multiply-and-divide/cc-7th-mult-div-negatives

I think using parentheses is certainly a good habit, but I don't believe it's strictly required when multiplying. However, there are other instances where this is necessary, such as raising a negative number to a power, for instance.

If you happen to come across any additional mistakes in the videos, you can follow the steps in this article to report the issue to our content team: https://support.khanacademy.org/hc/en-us/articles/212934867-How-do-I-report-mistakes-in-videos-

Additionally, if you notice any points of confusion, I encourage you to share your feedback and explanations with other users in our Tips & Thanks forums under the videos!

I hope this helps!