1)
[tex]2 \sqrt{3} - 5 \sqrt{3} = - 3 \sqrt{3} [/tex]
2)
[tex] - 4 \sqrt{7} + 10 \sqrt{7} = 6 \sqrt{7} [/tex]
3)
[tex] - 10 \sqrt{2} - 15 \sqrt{2} = - 25 \sqrt{2} [/tex]
4)
[tex]( + 3 \sqrt{5} ) + ( - 4 \sqrt{5} ) = [/tex]
[tex] = 3 \sqrt{5} - 4 \sqrt{5} = - 1 \sqrt{5} [/tex]
5)
[tex]( - 7 \sqrt{7} ) - ( + 10 \sqrt{7} ) = [/tex]
[tex] = - 7 \sqrt{7} - 10 \sqrt{7} = - 17 \sqrt{7} [/tex]
6)
[tex]3 \sqrt{2} - 7 \sqrt{6} + 5 \sqrt{6} - 10 \sqrt{2} = [/tex]
[tex] = - 7 \sqrt{2} - 2 \sqrt{6} [/tex]
7)
[tex]12 \sqrt{8} - 7 \sqrt{32} = [/tex]
[tex] = 12 \sqrt{ {2}^{2} \times 2 } - 7 \sqrt{ {4}^{2} \times 2 } = [/tex]
[tex] = 12 \times 2 \sqrt{2} - 7 \times 4 \sqrt{2} = [/tex]
[tex] = 24 \sqrt{2} - 28 \sqrt{2} = - 4 \sqrt{2} [/tex]
