SOLUTION: 3x-5y=900 ,5x-9y=1300 then x=? and y = ?

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Question 992992: 3x-5y=900 ,5x-9y=1300 then x=? and y = ?
Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
system%283x-5y=900%2C+%0D%0A5x-9y=1300%29.

Multiply first equation by  5  and the second equation by  -3.  Then add. You will get

-25y + 27y = 5*900 -3*1300,

2y = 4500 - 3900 = 600.

y = 300,

x = %28900+%2B+5%2A300%29%2F3 = 2400%2F3 = 800.

Answer.  x = 800,  y = 300.