Question

square root(18)-sqrt(8) would that equal -sqrt(144) or sqrt(-144)

Answer 1

\[-4*\sqrt{18}-\sqrt{8}\]
this is what i'm trying to simplify.

Answer 2

Neither?
\[\sqrt{18} = \sqrt{9\cdot 2} = \sqrt{3^3 \cdot 2} = 3\sqrt{2}\]
\[\sqrt{8} = \sqrt{4\cdot 2} = \sqrt{2^2 \cdot 2} = 2 \sqrt{2}\]
\[\implies \sqrt{18} - \sqrt{8} = 3\sqrt{2} - 2\sqrt{2} = \sqrt{2}\]

Answer 3

Oh.

Answer 4

Well then it's a bit different, but you can still use what I wrote to figure it out.

Answer 5

Oh, except that the first part should read:
\[\sqrt{3^2 \cdot 2}\]
not \[\sqrt{3^3 \cdot 2}\]

Answer 6

So if \[\sqrt{18} = 3\sqrt{2}\]
Then \[-4\sqrt{18} = (-4\cdot 3)\sqrt{2}\]

Answer 7

etc.

Answer 8

this would end up to be
\[-12\sqrt{2}-2\sqrt{2} \] subtract these
the answers is
\[-14\sqrt{2}\] that seem right.

Answer 9

Yep.

Answer 10

cool thanks. appreciate your dedication to this site Polpak.