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

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iheartfoodBest ResponseYou've already chosen the best response.0
ummm is this algebra 2?
 one year ago

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

sommersquidBest ResponseYou've already chosen the best response.0
once i find the y , i put it in the the first equation right?
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
I 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 :)
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
sorry hold on lemme see if that person will come... ;/
 one year ago

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

jim_thompson5910Best ResponseYou've already chosen the best response.3
double everything in the second equation to get 8x + 2y = 114
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
and hi @apoorvk thanks for coming also!!! i appreciate it :)
 one year ago

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

jim_thompson5910Best ResponseYou've already chosen the best response.3
Now add the two equations 7x  2y = 21 8x + 2y = 114  15x + 0y = 135 Now solve 15x = 135 for x
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
well 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??
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
is that how you do it?? simplify it into one larger equation??
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.3
that's one way to do it, there is more than one way
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
okay, 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... ;/
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.3
you 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
 one year ago

sommersquidBest ResponseYou've already chosen the best response.0
x = 9 for my problem right? (:
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
oh okay cool :) soooo x=45??
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.3
you are correct, the answer to the first piece is x = 9
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
oops my bad nvm lol
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.3
hmm how did you get x = 45?
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.3
now that you know that x = 9, use this to find y
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
sorry by bad... lol it's 9 sorry!!
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
sooo you plug it in right??
 one year ago

iheartfoodBest ResponseYou've already chosen the best response.0
so y=21 ???? and x=9 ???
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.3
yes, pick any equation dealing with y and plug in x = 9 7x  2y = 21 7(9)  2y = 21 Solve for y
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.3
and yes, y = 21
 one year ago

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

jim_thompson5910Best ResponseYou've already chosen the best response.3
oh 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
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.3
yes either equation works
 one year ago

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

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