Solving Simultaneous Equations by Elimination Example 2

[go1chase1the1sun1set]

Is it possible to find x first instead of y?

[Zohaib18006]

Exellent explanation!

[alanismacarty02]

uh, i think i'll just read my math book...

[911fion]

dude this is like oh so confusin

[cherry2047ful]

ty u some much this helped ty

[UZAYR101]

Thanks!

[shugoi95]

Thanks, I understand now :)

[murder312]

i got a problem , i know what the guy in the video is talking about but i got this one question that i am trying to solve :

4X + 2Y=8

2X - 5Y=10

i tried every kind of method - i think these kinda of questions are a bit tough thats what i heard, be gratfull if u guys replayed

[TheJEWSTAINE]

@murder312 i got

x = 2.5

y = -1

put this back into the equation and see if it works :)

[ytfwongfu4life]

i have a maths test tommorow eek! but this is helping me a lot thx

[Emmaishness]

Thank you so much! I was getting so frustrated with my homeworkd and this helped a lot! :)

[miley746]

How did you find 205 and 129 in the first part of your answer? please tell me i am so confused :(

[cherry2047ful]

@miley746 he to 205 by 5x41 which is 205 and he got 129 by 3x43 which is 129 hope i helped

[halfemoshit]

You make it sound sooooooooo easy.

[SHINeeTaeminForever]

why do you sub into 1 ??? not 2?

[cherry2047ful]

@SHINeeTaeminForever he was just labeling the equations 1 and 2 to make it easy for him when solving the equation hope i helped

[SHINeeTaeminForever]

@cherry2047ful yeah thank you :) i figured that out 

[TheLizamoon]

Thank God for LiveMaths. But I know I'm gonna fail that exam tomorrow. Fml.

[Thechubbygirl69]

@TheLizamoon Lolz.

[crazyolba]

Thank You very much sir! 

[fun2collect]

thank you soo much, really!! :)

[JayMamaDoc]

You explain better then my 60 yr old teacher thank you!!

[philigall20]

How did you get 205 and 129?? Thanks

[coolmn786]

@philigall20

you times it by 5 member

[AnimeLover1496]

5 people are dumb fuks

[wobb69]

As an Adult returning to education and never having done these at school i found them nearly impossible, I have struggled with these since september until i came across this video. You explain these equations so simply i could actually work them out after looking at the video only twice. Hail Silversafe..... you are a GOD. thank you so much. I have subscribed and look forward to the rest of your videos.... Thanks again.......

[sabrinagirl6]

This is really helpful!

thank you so much!

[Acurtx]

how do u know how to x the eqations by 3 and 5?

pleassss help me, i hav an exam on mondai!

[Darren4112]

How do you know which numbers to multiply ?

Like in your 1st vid you use the Y's and in this the X's

How do you know which ones to multiply ?

I have a test a really need help :P

[TheWargasmic]

very good!

[Lina15ful]

i dnt understand how 5x and 15y can = 205?, explain please peoples =)

[Suzizan]

@Lina15ful he multiplied the 41 by 5

[Turkishagent]

Beautiful explanation..

[TheNakedQuack]

Thumbs up if you are watching this video in preparation for a maths exam!

[tonnyrocks123]

@TheNakedQuack LOL mate. I am not preparing for an exam, but im trying to be AHEAD of the class :). u do deserve a THUMBS UP :D . Cheers

[Tukfssr]

how do you know what number to multiply by say why not multiply by 3

[MrBla342]

Great video by the way, slow and understandable

[greencherrybutterfly]

thanks, that was very helpful!

[thebestcoop14]

what do you do if the signs (+) are different?

[MrBla342]

@thebestcoop14

If it is different, you subtract the answers

[smallfartevan]

to get the same number of Y in both equations. i'm not sure if you could do:

(1) x 2 and

(2) x 5 to get the same number of X

[tven99]

yeah good question how n why did you multiply the first equations by 5 n the second one by three?? please tellme someone!

[NurKhan95]

why didnt u say u was using y ? even i got confused explain next time thanks good work though

[NurKhan95]

why did you x5 in the begining

[MrBla342]

@NurKhan95 To make y the same

[NurKhan95]

@MrBla342 no i sed that why didnt he say that he was using y

[7orqu3]

got it ha ha fucken delighted

[Moncheribabe]

im confused where you get the 5 and 3 from :S

[MrBla342]

@Moncheribabe He does that to make y the same and make things easier

[Bobafett4796]

Where the hell do the three and the five come from?

[wimbles222]

@Bobafett4796 they are the values of y, 3y and 5y, right?

[leedonaldt]

@Bobafett4796 the 3y and the 5y

[1234LMAO12345]

@Bobafett4796 hes refering back to the origanal question, douche.

it has a 3y in it

[TheHellboy123123]

Yo Blad. You x them by 5 and 3 to get the same number of Y's. They are from the equation. 5y, 3y ? You x opposite if you know what i mean.

[cycloneash]

@Bobafett4796

A late reply but i'll say it anyway

your finding the numbers lowest common factor

[Gurunarnak]

@Bobafett4796 you times by 5 and 3 to make them both 15y so the values of y are the same

[youruniquestyle]

@Bobafett4796 Lowest common multiple of 5 and 3, since 5 and 3 do not go into each other you have to find their lowest common multiple which is 15. To get 15 from 5 you have to multiply by 3 and to get 15 from 3 you have to multiply by 5.

[FreshApplePieOnXBL]

@Bobafett4796

You have to multiply each number by the coefficient of the values you're trying to eliminate

you need to get the coefficient of the valuues the same so that you can add/subract them to make them go away

[ludwindadougiefan]

whered you egt the 205..ive got a maths exam 2 mrrw so i need help badly

[bassSoloij]

41 x 5 = 205

[ceskazbrojovka17HMR]

once again mate i got this straight away, whereas my maths teacher couldnt show us how to do it this easily

[funnyfil]

same here mate

[poweroftheatom]

the way its explained is hard isnt there an easier way!

[0507jayesh]

thanks, ive got my maths gcse 2day

[zahid43]

he said same=subtraction therefore 15y in equation (1) and (2) were tooken away but 25x and 6x arre not the same so u shud add but he never?

[moila04]

Thanks your a genius! got my gcse maths on monday!

[PS3Comedy]

great help :D

[Hasnathz23]

what is both center values are letters?

[epicswell]

Thanks man, im doing linear algebra in computing science and this is giving me a great grounding on what we covered..cheers.

[InSuperb08]

It really helped me alot ! Thanks

[jonnycsmith]

This is good

thanks

any higher stuff like AS or A2?

cheers

[elizabeth3232]

should we do this hard explanation??

I know the answer, but I can't explan it;;

[louarmour]

Raspberry, He wanted to make equal amounts of y so he looked at 3y and 5y and thought of the lowest number that 3 and 5 go into. Well, 3 and 5 both go into 15. So he multiplied everything in (1) by 5 so he could get 15y and everything in (2) by 3 so he could again get 15y. Hope that helps.

[latinpapi1]

Now that I am slightly older and my brain has developed, I cant beleive I didnt undertand and memorize this....childsplay

[RosserD18]

This is junior cert. ordinary level maths.. Have you got Higher level Simultaneous Equations...?:D

[JaiJohneyuk]

damn it! thanks mate! ur a great teacher come 2 british school of bahrain please! our teacher is good but ur much better!:D give us more videos about maths pls! need 2 study more for IGCSE!:D

[silversafe]

You need to get the number of y the same so that when you subtract the equations, y disappears. (1) currently has 3y and (2) has 5y so you multiply (1) by 5 and (2) by 3 so that you get 15y in both equations.

[diddlestupid]

How did you get 5 and 3 to multiply them?

[latinpapi1]

In case it hasnt been answered....you attempt to reach the lowest common number for the Y part of the equation

[diddlestupid]

I agree with Raspberrydoe!

i don't understand how did you get 5?

where is it from? or it just a random #?

[lavadog40]

That was an awesome video, I understood everything :) Thank you :D

[chousita]

awesome work!!!!!!!!

so easay to understand!!

[casablanca55555]

OM to the G I lovee you.

thx:)

[latinpapi1]

OMG, i owe you one BIG TIME---Suscribing

[ktmad]

I love you more than the person below :P! Cheers, my maths tutor won't shout at me now!

[chuckiies88lover]

I LOVE YOU!!! =D

[ChopsticksKilla]

thanks alot

[Livemathsisthebest]

Another great video - go to the website - they are fab. Even my parents can understand what they are teaching.