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 2 years ago
What is the value of the x variable in the solution to the following system of equations?
7x  2y = 21
4x + y = 57
 2 years ago
What is the value of the x variable in the solution to the following system of equations? 7x  2y = 21 4x + y = 57

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iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0ummm is this algebra 2?

sommersquid
 2 years ago
Best ResponseYou've already chosen the best response.0algebra 1, 2nd year taking it again

sommersquid
 2 years ago
Best ResponseYou've already chosen the best response.0once i find the y , i put it in the the first equation right?

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0I think so... i asked somebody if they could come and help since I need to understand this better as well since i sort of forgot haha :)

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0sorry hold on lemme see if that person will come... ;/

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0Hi @jim_thompson5910 thanks for coming :) I also do not understand this 100% haha :) u got my message then i take it? :)

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3double everything in the second equation to get 8x + 2y = 114

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0and hi @apoorvk thanks for coming also!!! i appreciate it :)

apoorvk
 2 years ago
Best ResponseYou've already chosen the best response.0ohkay, @iheartfood  go on and post what you would have done in this problem, and don't worry if it's right or wrong.. :)

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3Now add the two equations 7x  2y = 21 8x + 2y = 114  15x + 0y = 135 Now solve 15x = 135 for x

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0well i know you're supposed to solve for one, but i did not know you could do that (what @jim_thompson5910 wrote.... so that is another way you can do it??

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0is that how you do it?? simplify it into one larger equation??

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3that's one way to do it, there is more than one way

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0okay, what's another way to do it?? i think i remember that you can solve one equation and then plug it in but i couldn't do it for this one... ;/

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3you isolate one variable in terms of the other then you substitute 4x + y = 57 y = 57  4x  7x  2y = 21 7x  2(574x) = 21 Now solve for x

sommersquid
 2 years ago
Best ResponseYou've already chosen the best response.0x = 9 for my problem right? (:

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0oh okay cool :) soooo x=45??

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3you are correct, the answer to the first piece is x = 9

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3hmm how did you get x = 45?

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3now that you know that x = 9, use this to find y

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0sorry by bad... lol it's 9 sorry!!

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0sooo you plug it in right??

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0so y=21 ???? and x=9 ???

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3yes, pick any equation dealing with y and plug in x = 9 7x  2y = 21 7(9)  2y = 21 Solve for y

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3and yes, y = 21

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0oh i used the second equation.. haha but it works both ways :) u get the same answer for both right?

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3oh the question was just "What is the value of the x variable in the solution to the following system of equations?" so they just want x Usually, they'll want both x and y

jim_thompson5910
 2 years ago
Best ResponseYou've already chosen the best response.3yes either equation works

iheartfood
 2 years ago
Best ResponseYou've already chosen the best response.0oh okay cool! thanks!! i totally understand it now... :) what a refresher!! And @sommersquid did that help??? And thanks again for coming @jim_thompson5910 :)

sommersquid
 2 years ago
Best ResponseYou've already chosen the best response.0yesss, it really did (: i just needed help with the second step but i got it now (: thank you so much everyone
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