-0,5×а+(-0,5)×в+(-0,5)×(-5,8)=-0.5а+0.5в+2,9
14х-х-28=167
13х-28=167
13х=167+28
13х=195
х=195:13
х=15
проверка
14*15-15-28=167
210-15-28=167
167=167
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(29,3-х)+54=69,351
29,3-х=69,351-54
29,3-х=15,351
х=15,351-29,3
х=13,949
проверка
(29,3-13,949)+54=69,351
15,351+54=69,351
69,351=69,351
-0.5а×(-7в)×(-2с)= -(0.5×7×2)×авс=-7авс
43*52=2236 3436-2236=1200. 1200:48=25 Ответ: 25 лошадей в фермерское хозяйстве.
1) 15 3/8 : (2 3/4х + 5 5/6) - 1 1/2 = 3/4
15 3/8 : (2 3/4х + 5 5/6) = 2 1/4
2 3/4х + 5 5/6 = 15 3/8 : 2 1/4
2 3/4х + 5 5/6 = 123/8 * 4/9
2 3/4х + 5 5/6 = 6 5/6
2 3/4х = 1
11/4х = 1
х = 4/11 => доказано
3 1/3 - (4 1/5х + х) : 5 4/7 = 8/15
3 1/3 - 5 1/5х = 8/15 * 39/7
3 1/3 - 5 1/5х = 8/5 * 13/7
26/5х = 3 1/3 - 2 34/35
26/5х = 3 35/105 - 2 102/105
26/5х = 350/105 - 312/105
26/5х = 38/105
х = 38/105 * 5/26
х = 19/21 * 1/13
х = 19/273
Может, ошибка в условии, но х не = 3.