[tex]a)\left \{ {{x=1-2y} \atop {2x+8y=3}} \right. = \left \{ {{x=1-2y} \atop {2(1-2y)+8y=3}} \right. =\left \{ {{x=1-2*\frac{1}{4} } \atop {y=\frac{1}{4} }} \right. =\left \{ {{x=\frac{1}{2}} \atop {y=\frac{1}{4} }} \right.[/tex]
[tex]b)\left \{ {{3x-2y=1} \atop {x=\frac{3}{2}-4y } \right. =\left \{ {{3(\frac{3}{2}-4y)-2y=1} \atop {x=\frac{3}{2} }-4y} \right. =\left \{ {{y=\frac{1}{4} } \atop {x=\frac{3}{2} }-4y} \right. =\left \{ {{y=\frac{1}{4} } \atop {x=\frac{3}{2} }-4*\frac{1}{4} } \right.=\left \{ {{x=\frac{1}{2} } \atop {y=\frac{1}{4} }} \right.[/tex]
