Answer:
x= 1/2
y=3
Explanation:
it is easier to subtract both equation and obtain a new one
1) 6x+0.4y=4.2
2) -4x+0.4y=-0.8
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1) -2)= 10x+0=5 leading to x=1/2
Now just eval x=1/2 in any of the original equations, for instances
1) 6*(1/2) +0.4*y=4.2, which leads to y=3