3x+4xy-3x+9xy-5xz+9-xz-1=13xy-6xz+8
Chúc hok tốt
3x+4xy-3x+9xy-5xz=9-xz-1
=(3x-3x)+(4xy+9xy)-(5xz+xz)+(9-1)
=13xy-6xz+8
Ta có:
\(3x+4xy-3x+9xy-5xz+9-xz-1\)
\(=13xy-6xz+8\)
\(3x+4xy-3x+9xy-5xz+9-xz-1\)
\(=(4xy+9xy)+(3x-3x)+(-5xz-xz)+(9-1)\)
\(=13xy-6xz+8\)
Chúc bạn học tốt