3 akar 20 - 2 akar 45 + akar 80 - 4 akar 125 =... ??

[tex]3\sqrt{20}-2\sqrt{45}+\sqrt{80}-4\sqrt{125} \\ 3\sqrt{4.5}-2\sqrt{9.5}+\sqrt{16.5}-4\sqrt{25.5} \\ 6\sqrt{5}-6\sqrt{5}+4\sqrt{5}-20\sqrt{5}=-16\sqrt{5}[/tex]

3√(4 x 5) - 2√(9 x 5) + √(16 x 5) - 4√(25 x 5)
= 6√5 - 6√5 + 4√5 - 20√5
= - 16√5