Jawabanmu

2014-09-09T17:54:17+07:00
2014-09-09T17:57:40+07:00
42n+35m+7-50m-20n+9
= 35m-50m-42n-(-20n)+7-9
=35m-50m-42n+20n+7-9
= -15m+62n-2
sory jika ada kesalahan tanda soalnya baru belajar