# How do you combine like terms in (4x ^ { 2} - 2x - 6) - ( x ^ { 2} + 3x - 4)?

Mar 11, 2017

Just open the brackets. See below:

#### Explanation:

Here you have : $\left(4 {x}^{2} - 2 x - 6\right) - \left({x}^{2} + 3 x - 4\right)$

Now I'm opening the brackets to achieve like terms. To open the brackets just multiply the 'sign' which is in front of the bracket with each and every term inside it.

Like here, for first bracket set,$+$ is in front of it so no change of symbols of numbers inside it,, so after removing brackets all the terms will remain same.

For the second set of bracket ,$-$ is in front of it means all the symbols of the numbers inside it will be reversed ( positive will become negative and negative will become positive).

So after opening brackets it will become:

$4 {x}^{2} - 2 x - 6 - {x}^{2} - 3 x + 4$
$= 3 {x}^{2} - 5 x - 2$ ( final answer)

hope it helps.