两式相减得,3y = 6m + 3
所以y = 2m + 1
1式乘以2与2式相加得,3x = 18m - 3
所以x = 6m - 1
代入2x - 5y = 4得
12m - 2 - 10m - 5 = 4
2m = 11
所以m = 5.5