Solve the equations 2s+3t=-1,t=4s-1 2b-4b=-1,2s+b=4 2m+3n=3m-2n=3 0.2x +0.3y=0.2 ,0.4x +0.1y=0.4

1.s=1/7 t=7
2.s=7/4 b=1/2
3.m=15/13 n=3/13
4.x=1 y=0

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