Question

Solve the following simultaneous equation x+2y=7,2x+y=2

Answer 1

2 x + 4 y = 14
2 x + 1 y = 2
-------------------subtract
3 y = 12
y = 4
go back for x
x = 7 - 2 y = 7 - 8 = -1
------------------
check
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x +2y = -1+ 8 = 7 yes
2 x + y = -2 + 4= 2 yes