3x-5y=0,2x-3y=1 和 9x-13y=-12,x+3y=2
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3x-5y=0,2x-3y=1 和 9x-13y=-12,x+3y=2
1
3x-5y=0,①
2x-3y=1 ②
①-②得
x-2y=-1;③
②-2×③得
y=3;
将y=3代入③解得
x=5.
2
9x-13y=-12①
x+3y=2②
①+②得
10x-10y=-10;
→x-y=-1③
②-③得
4y=3;
→y=3/4;
将y=3/4代入③解得
x=-1/4
3x-5y=0,①
2x-3y=1 ②
①-②得
x-2y=-1;③
②-2×③得
y=3;
将y=3代入③解得
x=5.
2
9x-13y=-12①
x+3y=2②
①+②得
10x-10y=-10;
→x-y=-1③
②-③得
4y=3;
→y=3/4;
将y=3/4代入③解得
x=-1/4
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