Question

9х+10=0
-9х+9=-8
-3х+5=7х
х+12=4х

Answer 1

9X + 10 = 0 
9X = - 10 
X = - 10/9 = - 1 1/9
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- 9X + 9 = - 8 
- 9X = - 17 
X = 17/9 = 1 8/9 
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- 3X + 5 = 7X 
7X + 3X = 5 
10X = 5 
X = 0,5 
---------
X + 12 = 4X 
4X - X = 12 
3X = 12 
X = 4