Question

help im confuse
simplify each sum or difference

9. sqrt 5 + 6 sqrt 5
11. 7 sqrt 3 + sqrt 3
13. 3 sqrt 7 - sqrt 63

Answer 1

For numbers 9 and 11, you can factor out the square root, ie

\[9) \ \ 1\sqrt{5}+6\sqrt{5} = (1+6)\sqrt{5}\]

Answer 2

For the last one, you can simplify square root 63

\[\sqrt{63}=\sqrt{7*6}=\sqrt{7}\sqrt{6}\]
so your final "simplification" will have the square root 7 factored out like up above

^_^


Follow?

Answer 3

im following

Answer 4

so! what would the answer to number 9 be? ^^

Answer 5

5sqrt5

Answer 6

?

Answer 7

no 7 sqrt 5

Answer 8

yup yup !! Then how about #11?

Answer 9

im not sure

Answer 10

what could you factor out of those two terms like we did for #9?

Answer 11

63 = 9 x 7
not 7 x 6

Answer 12

i only got 42 so far

Answer 13

\[\sqrt{63}=\sqrt{9} \times \sqrt{7}\]

Answer 14

@shamil98 I REALLY should learn how to multiply one of these days :P Thanks!!

Answer 15

@blubbernuggin
How did you get 42?

Answer 16

oh, 6*7. Yeah, I'm sorry, that was my bad. Brain hiccup.

Answer 17

But that was for #13. Did you get 11 already?

Answer 18

im working on it. i think

Answer 19

hold on i think i got it

Answer 20

Also, I really do apologize for factoring that wrong :/

Answer 21

its ok i can multiply either so here is what i did
\[3\sqrt{7} - \sqrt{63} = 3\sqrt{7} - \sqrt{9 x 7} = 3\sqrt{7} - \sqrt{9} x \sqrt{7} = (3-3) \sqrt{7} =\sqrt{7}\]

Answer 22

cant*

Answer 23

number 13

Answer 24

close - you got the hard part. What's
\[3-3=?\]
?

Answer 25

3 - 3 is 0

Answer 26

yah, so
\[(3-3)\sqrt{7} = 0\sqrt{7} = 0\]

^_^

Answer 27

oooooooooooohhhhhhh. <.<

Answer 28

thank you i get it now

Answer 29

very welcome ^_^

Answer 30

hey wait can you help me one more time

Answer 31

sure

Answer 32

\[3\sqrt{45} - 8\sqrt20 = (3-8) \]

Answer 33

that all i got up to i dunno what to do after that

Answer 34

unfortunately you can't factor out the square root if it's not the *same square root, so you can't pull the 3 and the -8 out just yet.

You have to find a common factor in the radicals

What's are common factors of 20 and 45?

Answer 35

1 and 5 ?

Answer 36

noo just 5

Answer 37

yup yup, so what do you get when you factor out 5 from both of those? (like factoring the 63 into 6 and 9 in #13)

Answer 38

you mean 9 and 7 ? lol

Answer 39

0_o I do, I promise...

Answer 40

but i think 25? or is it 9 and 4?

Answer 41

Just checking to make sure you're paying attention, right? :/ :P

Answer 42

9 and 4 are correct!

So then you can finally factor out that square root 5 to get
\[3\sqrt{9}\sqrt{5}-8\sqrt{4}\sqrt{5}=(3\sqrt{9}-8\sqrt{4})\sqrt{5}\]
which you can simplify a little bit further

Answer 43

so is the next step 27 - 32?

Answer 44

those are still square roots of those numbers, so it'd be

\[3*3-8*2\]

Answer 45

so 9 - 16?

Answer 46

= -7\[= -7\sqrt{5}\]

Answer 47

yup yup yup ^_^

Answer 48

or is it -35

Answer 49

oh ok xD

Answer 50

we've gotten all conflabulated! :P -7 is right though ^_^

Answer 51

do the same steps apply with addition like for this problem?

Answer 52

like if it were 3+8 instead of 3-8?

Answer 53

if it were like this \[3\sqrt{45 }+ 8\sqrt{20}\]

Answer 54

do same steps still apply even though the symbol changed

Answer 55

most definitely. Factoring out the square root 5 has no effect on that sign, so the steps would be exactly the same.

Answer 56

alright cool i got this thanks now beyond you go helping more kids indeed of help!

Answer 57

in need*

Answer 58

^_^ nice workin' with ya, and holler if you need anything else!