How do you solve #-2x - ( x - 4) = - 8#?

2 Answers
Sep 8, 2017

#x=4#

Explanation:

Solve:

#-2x-(x-4)=-8#

Expand left side.

#-2x-x+4=-8#

Simplify.

#-3x+4=-8#

Subtract #4# from both sides.

#-3x=-8-4#

Simplify.

#-3x=-12#

Divide both sides by #-3#.

#x=(-12)/(-3)# #larr# Two negatives make a positive.

Simplify.

#x=4#

Sep 8, 2017

See a solution process below:

Explanation:

First, remove the parenthesis on the left being careful to manage the signs correctly:

#-2x - (x - 4) = -8#

#-2x - x + 4 = -8#

Next, combine like terms on the left side of the equation:

#-2x - 1x + 4 = -8#

#(-2 - 1)x + 4 = -8#

#-3x + 4 = -8#

Then, subtract #color(red)(4)# from each side of the equation to isolate the #x# term while keeping the equation balanced:

#-3x + 4 - color(red)(4) = -8 - color(red)(4)#

#-3x + 0 = -12#

#-3x = -12#

Now, divide each side of the equation by #color(red)(-3)# to solve for #x# while keeping the equation balanced:

#(-3x)/color(red)(-3) = (-12)/color(red)(-3)#

#(color(red)(cancel(color(black)(-3)))x)/cancel(color(red)(-3)) = 4#

#x = 4#