Question 666578
please solve the system of linear equation by elimination method
x-y/x+y=4/5
7x-13y=50
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x-y/x+y=4/5
cross multiply
5(x-y) = 4(x+y)
5x-5y = 4x+4y
x - 9y = 0
Times 7 -->
7x - 63y = 0
7x - 13y = 50
-------------- Subtract
0x - 50y = -50
y = 1
=================
x - 9y = 0
x = 9