解析:
{x-y=48...①
{6(0.9x-y)=9(x-30-y)...②
②式可化为:
2(-0.1x+x-y)=3(x-y-30)
将①式代入上式可得:
2(-0.1x+48)=3(48-30)
2(-0.1x+48)=3*18
-0.1x+48=27
0.1x=21
解得x=210
代入①式,可得:
210-y=48
解得:y=162
所以原方程组的解为:
{ x=210
{ y=162
解析:
{x-y=48...①
{6(0.9x-y)=9(x-30-y)...②
②式可化为:
2(-0.1x+x-y)=3(x-y-30)
将①式代入上式可得:
2(-0.1x+48)=3(48-30)
2(-0.1x+48)=3*18
-0.1x+48=27
0.1x=21
解得x=210
代入①式,可得:
210-y=48
解得:y=162
所以原方程组的解为:
{ x=210
{ y=162