ALGEBRA hellllpppppp meee PLEASE!!!?

Question

Im saposto figgure out these 3 problems

here they are




Subtract the polynomials.
Subtract (8x - 5) from (7x - 2).





Add the polynomials.
(4x5 - 9x4 - 9x3 - 6) + (3x5 - 6x4 - 4x3 + 9)



and finaly






Subtract the polynomials.
(4a2 - 8) - (-a3 + 10a2 + 10)

some help here would be much appriciated!! :)
oh and please excuse my horrid spelling

Answer 1

My guess is that you're getting lost in the signs. Other than that, these aren't hard problems.

May I suggest that whenever you see "subtract" or the subtraction symbol "-" as an operation, that you think "+ (-1) times."

For example:
Subtract (8x - 5) from (7x - 2).
That means (7x-2) - (8x-5), right?
Ok, using my idea, it becomes
[7x + (-1)(2)] + (-1)[(8x) + (-1)(5))]= Notice there's no more subtraction signs to worry about, only signed numbers.
[7x + (-2)] + [(-1)(8x) + (-1)(-5)] = Distributing (-1) across the binomial. And this step is VITALLY important if you expect this approach to work.
[7x + (-2)] + [(-8x) + (5)] =
7x + -8x + -2 + 5 =
(7 + -8)x + 3=
(-1)x + 3 =
-x + 3, or
3 + -x, or
3 - x

It might look like a whole lot of extra work. Actually, once you get used to thinking that way, you won't need to write down all the steps. But your head will still do them.

Something else to think about...
a + b = b + a
a - b ≠ b - a in most instances
But a + -b = -b + a always

Also, adding "LIKE whatever" is resolved when you remember that you're working with that distributive property, a(b+c)=ab+ac.
So if you add 3x³ + 5x² = (3x)(x²) + (5)(x²) your going to get (3x + 5)x², and that really doesn't help you too much... unless you're supposed to be factoring.

I'd guess that replacing "subtraction" with the addition of (-1) times, and absolute adherence to the distributive property could be two of the most important things you're ever going have to learn. And, once you have them, you hardly have to think about them. There really aren't that many "vital" things to know in math. Most of the stuff you'll remember just because you use it a lot. The rest you can look up if you don't happen to remember it off the top of your head. But there are a few things that are so important. I think these are two of them.

Answer 2

Subtract (8x - 5) from (7x - 2).
= (7x - 2) - (8x - 5) = -x +3
(4x5 - 9x4 - 9x3 - 6) + (3x5 - 6x4 - 4x3 + 9)
Add the similar terms :
= 7x^5 - 15 x^4 - 13 x^3 +3
(4a2 - 8) - (-a3 + 10a2 + 10)
= 4 a^2 -8 - a^3 - 10 a^2 - 10
Add the similar terms :
= - a^3 - 6 a^2 -18

Answer 3

Is the first one (7x -2 ) - (8x - 5)?
(7x -2 ) - (8x - 5) =
7x - 2 - 8x + 5 =
-x + 3

If it's (8x - 5) - (7x - 2), then
(8x - 5) - (7x - 2) =
8x - 5 - 7x + 2 =
x - 3

(4x5 - 9x4 - 9x3 - 6) + (3x5 - 6x4 - 4x3 + 9) =
4x5 - 9x4 - 9x3 - 6 + 3x5 - 6x4 - 4x3 + 9 =
4x^5 + 3x^5 - 9x^4 - 6x^4 - 9x^3 - 4x^3 - 6 + 9 =
7x^5 -15x^4 -13x^3 + 3

(4a2 - 8) - (-a3 + 10a2 + 10)
4a^2 - 8 + a^3 - 10a^2 - 10
a^3 - 6a^2 -18

Just remember that when you are opening parentheses, if there is a minus sign in front of it, you have to multiply each term inside the parentheses by -1.

Answer 4

When adding and subtracting terms, you can always add the terms that have the same base variable and the same exponent.

So, in the first case, you have (7x-2)-(8x-5)

Now, it is important to note that whenever you have a minus sign in front of parentheses, it changes the sign of all the terms when you eliminate the parentheses. That's because it's like multiplying everything in the parentheses by -1. So, you get:

7x-2-8x+5 = (7-8)x + (5-2) or -x+3

In the second case, you get:

(4+3)x^5 + (-9-6)x^4 + (-9-4)x^3 + (9-6)

7x^5-15x^4-13x^3+3

As for the last case, you get after subtracting (remember to change the signs of the terms in the parentheses on the right):

4a^2-8+a^3-10a^2-10 or

a^3-6a^2-18

Answer 5

Subtract (8x - 5) from (7x - 2)
(7x - 2)-(8x - 5)= 7x-2-8x+5=3-x
Add the polynomials.
(4x5 - 9x4 - 9x3 - 6) + (3x5 - 6x4 - 4x3 + 9)=
7x^5-15x^4-13x^3+3
Subtract the polynomials.
(4a2 - 8) - (-a3 + 10a2 + 10)
4a^2-8+a^3-10a^2-10 =a^3 -6a^2-18

Answer 6

I'm not going to give you the answers as you should be able to do it yourself (otherwise it's cheating). But I'll explain how to do these, they're easy.

Whenever performing addition or subtraction with polynomials, just pay attention to the powers of the numbers. 4x^5 has a power of 5; 9x^34 has a power of 34, 8x has a power of 1 and is the same as 8x^1 since any number to the power of 1 is just that number itself; and a constant such as 10 is the same as 10x^0 since any number to the 0 power is equal to 1.

With that in mind, you can ONLY add and subtract numbers with LIKE POWERS. So you can add and subtract 4x^5 and 10x^5, but with any power other than 5, you cannot add or subtract them. And when performing this addition or subtraction, you are ONLY changing the COEFFICIENT, that is, the constant multiplying the variable, or the 9 on 9x^3.

So here's an example problem, notice how I only add like powers of the variables:

(9x^5 - 4x^3 + 3x) + (2x^5 + 8x^4 - 4x - 7)
= (9+2)x^5 + 8x^4 - 4x^3 + (3-4)x - 7
=7x^5 + 8x^4 - 4x^3 -x - 7

That is the answer in simplest form. Notice how there were only 2 like powers in the two polynomials I added: x^5 and x^1 (or x).

Same rules apply everywhere. Just remember to keep the correct positive or negative signs on the coefficients when performing these operations.

Answer 7

Subtract (8x - 5) from (7x - 2).
( 7x - 2 ) - ( 8x - 5 )
= 7x -2 - 8x + 5 = -x + 3

(4x5 - 9x4 - 9x3 - 6) + (3x5 - 6x4 - 4x3 + 9)

= 7x5 -15x4 -13x3 + 3
(4a2 - 8) - (-a3 + 10a2 + 10)
= 4a2-8+a3-10a2-10
= a3 -6a2-18

Answer 8

#1 if the question is

(8x-5)-(7x-2)

you will multiply by (7x-2) by -

8x-5-7x+2
and you will end up with x-3


#2 just add up the same terms ( I am assuming you mean 4x to the power of 5)

so you will end up with 7x^5 -15x^4 -13 x^3 + 3


#3 since you have a - before the second parhentesis you have to multiply it by the -

so you will have 4a^2 -8 +a^3 -10a^2 -10

your answer will be

a^3 - 6a^2 -18

hope this helps :)

Answer 9

ok, see the place the = sign is? in actuality, once you're taking a selection to the different edge of it, it does the alternative. 2e - 3 = 12 - 3e -ok so we could "carry mutually like words" get the numbers with an 'e' on one edge 2e + 3e = 12 + 3 -Now right here, the 3e has grow to be + because of the fact it has went over the = sign to do the alternative. additionally, the -3 has swapped too suited? and as you will discover that's now +3. 5e = 15 -ok so, i've got further them mutually and now we'd desire to discover out what e equals. suited now the 5 is multiplying the letter e. the alternative of multiplying is diving. e = 15 ÷ 5 e = 3 - that's your very final answer! try the different 2 your self now, and the instructor is right w = 6 because of the fact while -2w is going over the = sign it is going to become +2w. you will take care of do no longer subject, purely remember while a cost does over the = sign it does the alternative. helpful will become adverse, Multiplying will become dividing. desire this enables :)

Answer 10

when add, just ADD THEM LIKE IN 1ST GRADE.
when subtracting, add the opposite so just add -7x+2 to 8x-5