Question

a)14+7x-x=16-x b)20+5-4x=8-10 c)10x+x-9x=15-x

Answer 1

a)
14 + 7x - x = 16 - x
14 + 6x = 16 - x
6x + x = 16 - 14
7x = 2
x = 2/7
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b)
20 + 5 - 4x = 8 - 10
25 - 4x = - 2
25 + 2 = 4x
27 = 4x
4x = 27
x = 27/4 
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c)
10x + x - 9x = 15 - x
11x - 9x = 15 - x
2x = 15 - x
2x + x = 15
3x = 15
x = 15/3
x = 5

Answer 2

$a)~14+7x-x=16-x\to\\\\ 7x~-\not x+~\not x=16-14\to \\\\ 7x=2\to \\\\ \boxed{x= \frac{2}{7} }$




$b)~20+5-4x=8-10\to\\\\ -4x=8-10-20-5\to \\\\ -4x=-27~(-1)\to \\\\ 4x=27\to \\\\ \boxed{x= \frac{27}{4} ~ou~x=6,75}$




$c)~10x+x-9x=15-x\to \\\\10x+x-9x+x=15\to \\\\ 12x-9x=15\to \\\\ 3x=15\to \\\\ x= \frac{15}{3} \to \\\\ \boxed{x=5}$