Номер 217,218.Под знаками а),б)Фото прилагается.Помогите безотлагательно.

217)

1/2x - 7/16x = -5/8 - 3/4
8/16x - 7/16x = -5/8 - 6/8
1/16x = -11/8
x= - 11/8 * 16
x= -22
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7/12x + 1/6x =  2/3 -5/9
7/12x + 2/12x = 6/9 - 5/9
9/12x = 1/9
x = 1/9 * 12/9
x= 4/27
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218)

3/7x + 11/14x = 5/12 - 3/4 
6/14x + 11/14x = 5/12 - 9/12
17/14x = -4/12
x = -1/3 * 14/17
x = -14/51
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-1/5x - 19/50x = 9/10 - 7/25
-10/50x - 19/50x = 45/50 - 14/50
-29/50x = 31/50
x = -31/50 * 50/29
x = -31/29
x = -1 2/29
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