Simplify binomial trinomial all that junk hw help?

Question

1. [12-(3x+4)]-[7+(8-9x)] the answer is 6x-7 i just need to know the steps for the way there.
2. 7-3x squared - (12-[4-(3x squared+1)+2]-3x squared. The answer is -3x squared. Once again just the steps i need

Thanks in advance.

Thanks in advance

Answer 1

Alright I can help:

#1:
Easier than #2.
we see the equation:

[12-(3x+4)]-[7+(8-9x)]

The first step in simplifying is to expand any multiplication (or division) terms that we have. In this case we have two:
-1*(3x+4) and -1*[7+(8-9x)]

Expanding we get:

12 - 3x - 4 - 7 - 8 + 9x

Now we just combine like terms:

6x -7

Vola

#2
The same simple idea: expand any multiplication terms and then combine like terms, so:

7-3x^2 - (12-[4-(3x^2+1)+2]-3x^2)

Expanding we get:

7-3x^2 - 12 + 4 - 3x^2 - 1 + 2 + 3x^2

Simplifying:

7 - 12 + 4 - 1 + 2 -3x^2 + 3x^2 - 3x^2

again:

-3x^2

vola


good luck

Answer 2

1. =12-3x-4-(7+8-9x) = 12 -3x-4-7-8+9x = 12-4-7-8-3x+9x = -7+6x

Try to figure out the second one by working the information within the parantheses first then combine like terms. Then just follow the math operations. Use my solution as an example.

Good luck on your homework!

Answer 3

#1 First you need to distribute the negatives on the outside of the parenthesis and brackets:

(12-3x-4)-7-8+9x
This changes some of the signs

then you combine like terms in the parenthesis and out
8-3x-15+9x

then you combine all the like terms
6x-7

#2 You are missing a parenthesis, which my change the outcome of the anwer

Answer 4

1) [12-(3x+4)] - [7+(8-9x)]
(12 - 3x - 4) - (7 +8 -9x)

8-3x - 7 - 8 + 9x

-3x + 9x - 7

6x - 7

yay! :)

2) 7- 3x^2 - (12-[4-(3x^2 + 1) + 2] - 3x^2
7 - 3x^2 - [12-(4- 3x^2 - 1 + 2)] - 3x^2
7-3x^2 - (12 -(-3x^2 + 5)) - 3x^2
7 - 3x^2 -(12 +3x^2 - 5) - 3x^2
7 - 3x^2 -(3x^2 + 7) - 3x^2
7 - 3x^2 -3x^2 - 7 - 3x^2

7's cancel out
hmm...there must be a typo, cuz my 3x^2 don't cancel out!

Answer 5

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