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Solve using elimination.
5x + 2y = 7
10x + 4y = 14
ok so I am reteaching myself algebra 2, and I was doing this, would there be no solution? I am not sure If I did this correct.
 one year ago
 one year ago
Solve using elimination. 5x + 2y = 7 10x + 4y = 14 ok so I am reteaching myself algebra 2, and I was doing this, would there be no solution? I am not sure If I did this correct.
 one year ago
 one year ago

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jim_thompson5910Best ResponseYou've already chosen the best response.0
let z = 5x+2y
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.0
double both sides 2z = 2(5x+2y) 2z = 10x+4y
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.0
so if 5x + 2y = 7 10x + 4y = 14 then we can also say z = 7 2z = 14 where z = 5x+2y
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.0
but....what happens when we solve 2z = 14 for z?
 one year ago

liizzyliizzBest ResponseYou've already chosen the best response.0
I am not sure If I am thinking about this in the correct way, but technically wouldn't z would = 7. and we already know that. So I am a bit lost now, with where you're going with this.
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.0
2z = 14 > z = 7 but z = 7 in the first equation
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.0
so no matter what happens, we're going to get z = 7
 one year ago

jim_thompson5910Best ResponseYou've already chosen the best response.0
so because z = 5x+2y, this means that 5x+2y = 7 and this applies to both equations because the two are really the same equation
 one year ago

MertsjBest ResponseYou've already chosen the best response.2
The problem says to solve by elimination so multiply the first equation by 2 and then add the two equations. You will get the true statement 0=0 which tells you that there is an infinite number of solutions.
 one year ago

liizzyliizzBest ResponseYou've already chosen the best response.0
oh ok, I got the 0=0 but I wasnt sure if that meant infinite or no solutions. which is why I said no solutions. Ahh thank you for that clarification.
 one year ago

MertsjBest ResponseYou've already chosen the best response.2
If you got a nonsense statement such as 0 = 3, that would indicate no solution.
 one year ago

liizzyliizzBest ResponseYou've already chosen the best response.0
that makes more sense, I feel so silly now for confusing that.
 one year ago
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