Question

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

Answer 1

`-3x+2`

Explanation:

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`