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anonymous
 one year ago
what is the solution of
x+y=7
2x4y=8
anonymous
 one year ago
what is the solution of x+y=7 2x4y=8

This Question is Closed

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1we have a `y` in the first equation and a `4y` in the second equation adding them up gives: `y+(4y) = 3y` which isn't 0 like we want however we can change that `y` to `+4y` by multiplying by 4. Then notice how `4y + (4y) = 0y = 0`

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1to change the y to 4y, we have to multiply both sides of the first equation by 4 x+y=7 4*(x+y)=4*7 4x+4y = 28

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1This system x+y=7 2x4y=8 turns into 4x+4y=28 2x4y=8

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1Do you see how to solve 4x+4y=28 2x4y=8 ??

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1you add actually

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1add straight down 4x+4y=28 2x4y=8  6x+0y = 36 so 6x = 36 which means x = ???

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1now take that x value and plug it into any equation that has x and y in it

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1then solve for y

anonymous
 one year ago
Best ResponseYou've already chosen the best response.01247=8? am i doing that right?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1yes now solve for y
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