4. х = 3/26
5. х = 2/15
6. х = 10/7
Пошаговое объяснение:
4. 5(x) + 6 11/26 = 7
5х = 7 - 6 11/26
5х = 6 26/26 - 6 11/26
5х = 15/26
х = 15/26 : 5 = 15/26 * 1/5
х = 3/26
Проверим: 5*3/26 + 6 11/26 = 15/26 + 6 11/26 = 6 26/26 = 7
5. 3(x) : 13,2 = 1/33
3х = 1/33 * 13,2 = 1/33 * 13 1/5 = 1/33 * 66/5
3х = 2/5
х = 2/5 : 3 = 2/5 * 1/3
х = 2/15
Проверим: 3*2/15 : 13,2 = 6/15 : 13 1/5 = 6/15 * 5/66 = 1/33
6. 79+4:(x) = 81,8
4 : х = 81,8 - 79
4 : х = 2,8
х = 4 : 2,8 = 4 : 2 4/5 = 4 : 14/5 = 4 * 5/14
х = 10/7
Проверим: 79 + 4 : 10/7 = 79 + 4 * 7/10 = 79 + 28/10 = 79 + 2,8 = 81,8
4х+5х=72
х=8
4*8=32
5*8=40