I was frustrated at this, my last question and not sure how to do it properly. I just need guidance in any way. I tried grouping but I may have done it incorrectly.

Finding the difference of (−4x2 − 7x3 − 2) − (8x3 + 3x − 7x2).

Question

I was frustrated at this, my last question and not sure how to do it properly. I just need guidance in any way. I tried grouping but I may have done it incorrectly.

Finding the difference of (−4x2 − 7x3 − 2) − (8x3 + 3x − 7x2).

ivettef365 · Answer

first take out the parenthesis and you have

-4x^2 -7x^3 -2 -8x^3 -3x + 7x^2  now combine like terms

anonymous · Answer

this could be incredibly wrong( would not be surprised)  
-11^5 -2 - 4x

jdoe0001 · Answer

$\bf (-4x^2-7x^3 - 2) - (8x^3 + 3x - 7x^2)\ \quad \ \implies -4x^2 - 7x^3 - 2 - 8x^3 - 3x + 7x^2\\quad \\quad\
-4x^2 + 7x^2- 7x^3 - 8x^3- 2  - 3x $

jdoe0001 · Answer

keep in mind that $\bf \large   - (8x^3 + 3x - 7x^2) \implies -1 \times (8x^3 + 3x - 7x^2)$

ivettef365 · Answer

you can only combine terms that are equal, for example you can combine
-4x^2 -7x^2  both terms have x^2 so (-4-7= -11)  so combined it is -11x^2

anonymous · Answer

wow I was infact, so wrong on the grouping of like terms.

anonymous · Answer

so like in the example, the power ^2 had to be also the same to group aswell as the variable x?

jdoe0001 · Answer

yes

anonymous · Answer

I did not know that key factor! always that the variable ONLY had to be the same hah

ivettef365 · Answer

correct

jdoe0001 · Answer

that's true for multiplication, not so for subtractions or additions

anonymous · Answer

probably where my confusing made its way in.

anonymous · Answer

so, the combined like terms come together as  -11x^2? @ivettef365 
I got the steps from @jdoe0001  and need to make sure im not lost here.

jdoe0001 · Answer

$\bf \large \color{red}{-4x^2 + 7x^2}\color{blue}{- 7x^3 - 8x^3}- 2  - 3x$

ivettef365 · Answer

sorry it is -4x^2 +7x^2 so it is (-4+7= 3) so it is 3x^2

ivettef365 · Answer

now combine the numbers with x^3

anonymous · Answer

@jdoe0001  do I combine here aswell?

jdoe0001 · Answer

you combine, the like-terms, the terms whose variables are equal in letter and exponent

jdoe0001 · Answer

for example, -2 has no other constant equal in the surroundings, so it's left by its lonesome
-3x has no other term in with an "x" only, so it's also left by its lonesome

the other 2 pair, have companions

anonymous · Answer

3x2 - 15x3 -2-3x
so.. uhm 
where do i go wrong.

jdoe0001 · Answer

looks good

anonymous · Answer

so thats at its simplest form?

jdoe0001 · Answer

yeap

anonymous · Answer

wooooot!

jdoe0001 · Answer

heheh, anything wrong with it? heh

anonymous · Answer

Nope I think it makes sense :DD!!! THANK YOUU, praise the lorddd

jdoe0001 · Answer

yw