来自罗琼的问题
去括号:3a2-2(a-b-5c)=______;添括号:a+2b-4c-3d=a-______=______.
去括号:3a2-2(a-b-5c)=______;
添括号:a+2b-4c-3d=a-______=______.
1回答
2019-12-26 21:51
去括号:3a2-2(a-b-5c)=______;添括号:a+2b-4c-3d=a-______=______.
去括号:3a2-2(a-b-5c)=______;
添括号:a+2b-4c-3d=a-______=______.
3a2-2(a-b-5c)=3a2-2a+2b+10c,
a+2b-4c-3d=a-(-2b+4c+3d)=a+2b-(4c+3d),
故填3a2-2a+2b+10c;a+2b-(4c+3d).