Tìm x, biết

a) 3x(12x-4)-9x(4x-3)=30

b) x(5-2x)+2x(x-1)=15

I) Rearrange the words or phrases to make meaningful sentences

1. lending/ English books/ you mind/ me/ Would/ some/ ?

2. a local man/ named Ho Khanh/ in 1991/ by/ Son Doong Cave/ was/ discovered

3. together/ Family members/ live apart/ at Tet/ who/ try to be

4. their free time/ Teenagers/ often spend/ surfing/ the Internet/ most of

5. we can/ use/ motorbikes,/ If we/ public buses/ energy/ instead of/ save

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