another radical question?

Question

anonymous · Answer

5  radical 11 - 12 radical 11 - 2 radical 11
Help simplify please?

anonymous · Answer

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jim_thompson5910 · Answer

let x = radical 11

jim_thompson5910 · Answer

so you have 

5x - 12x - 2x

anonymous · Answer

You can treat rad 11 as any other variable. If you have five of something, subtract twelve of them, and subtract another two, how many will you be left with?

anonymous · Answer

@jim_thompson5910 so that would be the answer? the potential answers I have include the radical sign... :/

jim_thompson5910 · Answer

what does 5x - 12x - 2x simplify to?

anonymous · Answer

@vinnv226 I am not sure Im confused with what you mean ..

anonymous · Answer

@jim_thompson5910 -9x?

jim_thompson5910 · Answer

remember we let $\large x = \sqrt{11}$

jim_thompson5910 · Answer

so -9x turns into $\large -9\sqrt{11}$

jim_thompson5910 · Answer

so this means

$$\large 5\sqrt{11}-12\sqrt{11}-2\sqrt{11} = -9\sqrt{11}$$

anonymous · Answer

oh wow! that was easy haha I get it! so if the number under the square root sign is the same you just add/sub/whatever the other numbers?

jim_thompson5910 · Answer

exactly, think of $\large 5\sqrt{11}$ and $\large -12\sqrt{11}$ as like terms which can be combined

jim_thompson5910 · Answer

once you get in the habit, you won't have to replace the radicals with x, but it helps to do that to see what's going on

anonymous · Answer

wow thanks so much I actually understand most of the questions on this homework now :)

jim_thompson5910 · Answer

that's awesome, glad it's all clicking now

anonymous · Answer

how about though if the 3 is above the squareroot like this:

anonymous · Answer

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