Răspuns :
[tex](20 \sqrt{2} - 30 \sqrt{2} ) \div 10 = ( - 10 \sqrt{2} ) \div 10 = - 10 \sqrt{2} \div 10 = - 1 \sqrt{2} = - \sqrt{2} [/tex]
[tex](20 \sqrt{2} - 30 \sqrt{2} ) \div 10 = ( - 10 \sqrt{2} ) \div 10 = - 10 \sqrt{2} \div 10 = - 1 \sqrt{2} = - \sqrt{2} [/tex]