-4x + 7 - [(-3x +1) - (-2x - 4)] = ?

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Answer 1 · 2018-01-18T23:20:06

$-3x+2$

In order to solve this, we will first simplify the term in the square brackets, then complete the operation.

First, we examine the term in the square brackets.

$[(-3x+1)-(-2x-4)]$

Recall that $a-b = a+(-b)$ , thus $a+b = a-(-b)$ as well:

$= [(-3x+1)-(-1(2x+4))] = [(-3x+1)+2x+4]$

Now, we combine like terms:

$= [-3x+2x +1+4] = [-x+5]$

Substitute this back into the original equation for our term in the brackets:

$-4x+7 - [(-3x+1)-(-2x-4)] = -4x+7 - (-x+5)$

Once more, $a-b = a+(-b)$ ...

$-> -4x+7 + x-5 = -3x+2$