How do you simplify #(x-c)-(2x-4c)#?

2 Answers
Leland Adriano Alejandro
Apr 1, 2016

#(x-c)-(2x-4c)=-x+3c#

Explanation:

From the given #(x-c)-(2x-4c)=(x-c-2x+4c)=x-2x-c+4c#
#=-x+3c#

God bless....I hope the explanation is useful.

Tony B
Apr 1, 2016

#(x-c)-(2x-4c)" "->" "3c-x#

Explanation:

Consider #-(2x-4c)#

This is stating that everything inside the bracket is to be multiplied by #(-1)#

Technically you could write

#color(blue)((-1))color(brown)(xx(2x-4c))# but it is not considered to be good mathematical practice.

So we have #color(brown)(-(2x-4c)" " ->" " color(blue)((-1)xx)2x -color(blue)((-1)xx)4c)#

Notice we have two minuses together in the multiplication
#color(brown)(-color(blue)((-1)xx)4c)#. This gives us a positive. So the whole bracketed part of #-(2x-4c)# becomes: #-2x+4c#

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
So by removing the brackets we have:

#x-c-2x+4c#

Grouping like terms

#4c-c+x-2x#

Counting up all the #c's# we end up with #+3c#
Counting all the #x's# we end up with #-x#

Putting it all together

#(x-c)-(2x-4c)" "->" "3c-x#

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