Question

a) 3x-1y=1
2 4 4
1x+1y=1
3 8 6

Answer 1

Oi 

6x/4 - y/4 = 1/4
6x - y = 1

x/3 + y/8 = 1/6
8x + 3y = 4

sistema
6x - y = 1
8x + 3y = 4
18x - 3y = 3

26x = 7
x = 7/26

42/26 - y = 26/26

y = (42 - 26)/26 = 16/26 = 8/13

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