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anonymous
 5 years ago
solve using elimination method
5x+5y=7
7x2y=13
anonymous
 5 years ago
solve using elimination method 5x+5y=7 7x2y=13

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok, lets eliminate y, and find x first: to eliminate y lets multiply 1st eq by 2 and 2nd eq by 5, to make both Ys cancel each other out once subtracted, so we will have: 10x+10y=70 35x+10y=65 so now we have to subtract coresponding members in both eqs: 45x+0=5 45x=5 now divide both sides by a 45 to find x x=5/45=0.111

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0to find y just substitute it into any of the equations: 5x+5y=7 5*0.11111+5y=7 5y=7+0.5555 5y=6.44445 y=6.44445/5 y = 1.28889 y = 1.289

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0now lets see if I was correct, by substituting the values into any eq: 5x+5y=7 5*0.1111+5*1.289= =7 so I was right and the answers are correct

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0that doesn't work for the other equation...you messed up somewhere on top

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you didn't cancel out y because you had positive 10y on both equations instead of one positive and one negative so that only gave you the right answer for one equation

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok, so how do I do it?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0do the first equation the same but instead of multiplying second equation by 5 multiply it by 5 so you get 10x + 10y = 14 35x  10y = 65 this way y really is eliminated then you have 45x = 51 so x = 51/45 which is approximately 1.1333.... plug into either equation and solve 7(1.1333)  2y = 13 or 7.9331 2y = 13 after solving for y you get y = 2.53345 now check those two values in both equations
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