6х - ( 2х + 5) = 2(3х - 6)
6х - 2х - 5 = 6х - 12
4х - 6х = -12 + 5
- 2х = - 7
х = 3,5
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х(х - 4) = (х + 3)^2
x^2 - 4x = x^2 + 6x + 9
- 4x - 6x = 9
- 10x = 9
10x = - 9
x = - 0,9
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(a^2 - 8a + 16) / (ax- 4x) = (a - 4)^2 / x(a-4) = (a - 4)/x
a = - 5; x = -2
(- 5 - 4) / -2 = (- 9) / -2 = 4,5