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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