How do you solve $21 - (x + 9) = 8 x - 6 ?$ $21- ( x + 9) = 8x - 6?$

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Answer 1 · 2016-12-15T16:05:38

$x = 2$ $x = 2$

First, expand the term in parenthesis and then group and combine like terms on the left side of the equation:

$21 - x - 9 = 8 x - 6$ $21 - x - 9 = 8x - 6$

$21 - 9 - x = 8 x - 6$ $21 - 9 - x = 8x - 6$

$12 - x = 8 x - 6$ $12 - x = 8x - 6$

Now, isolate the $x$ $x$ terms on one side of the equation and the constants on the other side of the equation while keeping the equation balanced:

$12 - x + x + 6 = 8 x + x - 6 + 6$ $12 - x + x + 6 = 8x + x - 6 + 6$

$12 - 0 + 6 = (8 + 1) x - 0$ $12 - 0 + 6 = (8 + 1)x - 0$

$12 + 6 = 9 x$ $12 + 6 = 9x$

$18 = 9 x$ $18 = 9x$

Now solve for $x$ $x$ while keeping the equation balanced:

$\frac{18}{9} = \frac{9 x}{9}$ $18/9 = (9x)/9$

$2 = (cancel(9)x)/cancel(9)$

$2 = x$

How do you solve 21- ( x + 9) = 8x - 6?21−(x+9)=8x−6?21- ( x + 9) = 8x - 6?