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Answer 1 · 2016-10-01T11:17:04

Get rid of the fractions! Then solve.
$x = - 8 \frac{6}{9} = - 8 \frac{2}{3}$ $x = -8 6/9 = -8 2/3$

If you have an equation which has ONE fraction on each side of the = sign, then you can get rid of the fractions by cross-multiplying.

$\frac{(7 x - 1)}{5} = \frac{3 (5 + 2 x)}{3}$ $color(red)((7x -1))/color(blue)(5) = color(blue)((3(5+2x))/color(red)(3)$

You can multiply with either red or blue first. I have chosen to multiply the blue first, you will see why in the working. *

$5 \times 3 (5 + 2 x) = 3 (7 x - 1) \leftarrow$ $color(blue)(5xx3(5+2x)) = color(red)(3(7x-1))" "larr$ no fractions !

$75 + 30 x = 21 x - 3 \leftarrow$ $75 +30x = 21x-3" "larr$ bigger x on the left was predictable*

$30 x - 21 x = - 3 - 75$ $30x-21x = -3-75$

$9 x = - 78$ $9x = -78$

$x = - \frac{78}{9}$ $x = -78/9$

$x = - 8 \frac{6}{9} = - 8 \frac{2}{3}$ $x = -8 6/9 = -8 2/3$