Sharon Tham's answer to Justneedshelp's Secondary 1 Maths Singapore question.
You may refer to more material in my youtube channel:
https://www.youtube.com/channel/UCVB3iFkIXsInbvKP7HOjOOg
https://www.youtube.com/channel/UCVB3iFkIXsInbvKP7HOjOOg
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