i need help with factoring please :)

can anyone explain radicals to me...we have a test on it in school 2morrow and im lost

EDIT: now i need help with radicals

 

all I know is that they are square roots

 

lol yea i get that much but how do i do themfor example heres a problem

5 radical 82

 

fidn the highest number that u can sqaure into 82 ( 8 ) then i think u do like 5*8square root the difference betwwen 82 and 64

 

huh? :?

 

i think the answer is 40 root 18...but im not sure

 

wait so you said first i find the biggest square root of 82 then multiply that by the 5?

 

ya u find the largest root that will go into the square root (whole number) and then multiple it by the number outside then u take the differnce from the number under the root from the largest root and leave that under the sign

 

ooh i kinda get it now. thanks. when i get one rep point ill give you one for helping also if anyone knows how to do factoring can you explain it please. thanks

sorry these are the two topics i dont get AT ALL in math for some reason. everything else i get

 

i can help you with factoring if u give me a problem

 

ok for example the teacher gave us this problem.

15x squared+ 28x +14

 

ok, i cannot remember how to factor after seeing that problem sorry..im gonna look in my last semesters notes..

 

its ok ill see if any of my friends are online and ill ask them 4 help. if you find out how to do it just pm me or post on this board

 

can anyone help? im still online

 

well that is in simpelest form to my knowledge UNLESS x is defined as a number

 

I think he's right...because don't 2 numbers have to add up to the last number and multiple to equal the middle number like:

15x^2 + 14x + 9

And then you have 7 + 2 = 9 and 7*2=14?

 

Yep, as far as my High School education has taught me, that one's already in simplest form. If you have another problem you're stuck on I may be able to help.

 

Well, unless you use the quadratic formula...your answers will have radicals in them, though.


And regarding your edit, is there a specific problem you need help with?

 

1. look at the term under the radical
2. does it have any perfect square factors? (in this case no, since 82 = 2 * 41 and neither are squares)
3. if there is, divide what is under the radical (I think its called the radicand) by the perfect square and multiply what is in front of the radical by the square root of the square

examples...
4 radical 50 = 4 radical 2*25 = 4*5 radical 2
radical 124 = radical 4*31 = 2 radical 31

 

...

yay i feel so lucky my teacher was absent today so the test on mon!!!

ooh and that problem isnt in simplest form. x is supoused to stand for a number xD

EDIT: thanks lazypando for the help

is anyone able to help??? if not its ok