Respuesta :

altavistard

Answer:

-7√5

Step-by-step explanation:

I'll transcribe your verbal question into a symbolic one as best I can:

-2√20 - √125

Note how √20 = √4*√5 and √125 = √25 *√5.  Thus,

your -2√20 - √125, after we've factored √5 out of both terms, becomes

-2(2)√5 - 5√5, or -2√5 - 5√5, which combines to form

-7√5 (answer)


gmany

[tex]-2\sqrt{20}-\sqrt{125}=-2\sqrt{4\cdot5}-\sqrt{25\cdot5}=-2\sqrt4\cdot\sqrt5-\sqrt{25}\cdot\sqrt5\\\\=-2(2)\sqrt5-5\sqrt5=-4\sqrt5-5\sqrt5=\boxed{-9\sqrt5}\\\\Used:\ \sqrt{ab}=\sqrt{a}\cdot\sqrt{b}\ for\ a\geq0\ and\ b\geq0[/tex]

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