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$ 11x-7+8x = -3-9x$
$19x-7 = -3-9x$
$19x+9x = -3+7$
$28x = 4$
$\dfrac{\cancel{28}x}{\cancel{28}} = \dfrac{4}{28}$
$x = \dfrac{\cancel4^1}{\cancel{28}_7}$
$x= \dfrac{1}{7}$
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$ 10-x+6-17x-3x+8 = 0$
$ -21x +24 = 0$
$ -21x = -24$
$ 21x = 24$
$ \dfrac{\cancel{21}x}{\cancel{21}} = \dfrac{\cancel{24}^8}{\cancel{21}_7}$
$ x = \dfrac{8}{7}$