How do you solve $-( x - 5) = 3x - 15$ ?

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Answer 1 · 2017-03-30T01:57:17

See the entire solution process below:

First remove the terms on the left hand side of the equation from the parenthesis. Be careful to handle the signs of the individual terms correctly:

$-x + 5 = 3x - 15$

Next, add $color(red)(x)$ and $color(blue)(15)$ to each side of the equation to isolate the $x$ term while keeping the equation balanced:

$color(red)(x) - x + 5 + color(blue)(15) = color(red)(x) + 3x - 15 + color(blue)(15)$

$0 + 20 = color(red)(1x) + 3x - 0$

$20 = (color(red)(1) + 3)x$

$20 = 4x$

Now, divide each side of the equation by $color(red)(4)$ to solve for $x$ while keeping the equation balanced:

$20/color(red)(4) = (4x)/color(red)(4)$

$5 = (color(red)(cancel(color(black)(4)))x)/cancel(color(red)(4))$

$5 = x$

$x = 5$

How do you solve -( x - 5) = 3x - 15-( x - 5) = 3x - 15?