Пошаговое объяснение:
1. 4/a+7/b=4b+7a/ab
2. 9/m-5/mn=9n-5/mn
3. 4/12xy-11/18xy=12-22/36xy=-10/36xy=-5/18xy
4. 5m/3ab+2n5a^2b-7p/2ab^2=(50abm+12bn-105ap)/30a^2b^2
5. 3a-4b/a+8a^2+4b^2=(3ab-4b^2+8a^2+4b^2)/ab=(8a^2+3ab)/ab
6. 3c^2-2c+4/bc^2-(2c-9)/bc=(3c^2-2c+4-2c^2+9c)/bc^2=(c^2+7c+4)/bc^2
Пошаговое объяснение:
1. 4/a+7/b=4b+7a/ab
2. 9/m-5/mn=9n-5/mn
3. 4/12xy-11/18xy=12-22/36xy=-10/36xy=-5/18xy
4. 5m/3ab+2n5a^2b-7p/2ab^2=(50abm+12bn-105ap)/30a^2b^2
5. 3a-4b/a+8a^2+4b^2=(3ab-4b^2+8a^2+4b^2)/ab=(8a^2+3ab)/ab
6. 3c^2-2c+4/bc^2-(2c-9)/bc=(3c^2-2c+4-2c^2+9c)/bc^2=(c^2+7c+4)/bc^2