KingNuru23

Karma: 15

how to solve 4(x+3) + 6= 2x- (3+x)

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+1 Views: 743 Answers: 8 Posted: 12 years ago

8 Answers

robertgrist

Karma: 279491

There are things in life that you will never have to use in Heaven…algebra is one of those things.

12 years ago. Rating: 3
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jhharlan

Karma: 1457190

Geez, you are taking me back. Way too far back, I'm old now and don't have to figure out this type of problems anymore...

12 years ago. Rating: 2
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Bob/PKB

Karma: 945575

4(x + 3) + 6 = 2x - (3 + x)

4(x + 3) means to multiply (x + 3) by 4. 4 x "X" is 4X (I don't know what X is, but now I have 4 of them) and 4 x 3 is 12. 4x + 12 + 6

2x - (3 + x) means to subtract x from 2x and 3 from 2x. I can't add 3 and x together because I don't know how much X is and I can't subtract 3 from 2x because I don't know what x stands for, but I CAN subtract x from 2x. I'll have 1x left and will need to subtract 3 still. 1x can be written X. X-3

4x + 12 + 6 = x -3 I can add the 12 and 6. That makes 18!

4x + 18 = x - 3
Now my goal is to get a real number on one side of the equation and the X part on the other side. It doesn't really matter which side has the number and which has the unknown. But here's my thinking....

4x + 18 - 18 = x -3 -18
If I get rid of the +18 and I'll just have 4x. If I subtract 18 from the first part of the equation, I'll be left with 4X. But if I adjust the first part of the equation, I need to make the same adjustment to the second part of the equation. That's why I subtract 18 from both sides of the = sign.

4x = x -21
(a negative 3 and a negative 18 is negative 21). Now I need to get rid of the x in the second half of the equation. Then I will be able to figure out what X is!!! I will subtract x (or 1x) from each side of the equation. Then I will have the X on one side and a number on the other!

4x -x = x - x -21
If I subtract that x in "x-21", I will be left with -21 on one side of the equation. Since I am subtracting x from one side, I gotta subtract x from the other side. 4x - x is 3x

3x = -21
Now I know that 3 times X is -21. That tells me, first off, that my answer to "X" is going to be a negative number. Does that make sense?

3x/3 = -21/3
If I want to know how much 1 x is, I need to divide my 3x by 3, which will leave me with 1x (which I write as "x"). Again, if I am dividing one side by 3, I must do the same to the other side, to stay in balance! -21 divided by 3 is -7.

x = -7 I can check this and make sure it's right by putting -7 in all the places where x was in the first place.

4(-7 +3) + 6 = 2(-7) - (3 + -7)
Do the stuff in ( ) first.( THAT IS CALLED ORDER OF OPERATIONS, what you do first, then next then next). -7 + 3 = -4.    4 x -4 = -16.    Now I have -16 + 6
2 x -7 = -14 and 3 + (-7) = -4   Now I have -14 - (-4)

-16 + 6 = -14 - (-4)
Does that make sense? If you add a negative number, your "sum" decreases. If I say I have $3 in my pocket but I owe you $7, I really am $4 in the red. (-4). If I subtract a negative number, I INCREASE what I have. If I have $3 in my pocket but owe you $7 and you tell me to forget the loan, I have increased my cash to $10 because I DON'T have to give you the $7 anymore. I don't just have $3. I have an additional $7 because you gave it to me and didn't ask for it back, even if I don't have the $7 in my pocket.

-16 + 6 = -10
-14 - (-4) = -14 + 4 (subtract a negative means I add that amount. The way I remember to add a subtracted negative number is by noting there are two negative signs sitting next to each other. I take those two negative lines and turn them into a plus sign.....just my way of remembering) -14 + 4 = -10

-10 = -10

I hope this made at least a little bit of sense. It would be easier to work it out with you step by step. If something is unclear, let me know. I would love for you to be able to say "I GOT IT!!

12 years ago. Rating: 2
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arjit

niceeeeeeeee
but looks like u r a fresher

commented 12 years ago

mycatsmom

Very confusing.

commented 12 years ago

Bob/PKB

I can write out the thought process for each step if you really want to know...........

commented 12 years ago

Tommyh

You're some teacher Bob.

commented 12 years ago

mycatsmom

to Bob/PKB yes, do write out the thought process. I often think about how I wished I could have learned algebra. I was thinking of it yesterday , before I read this entry. My teacher never taught how to do the thought process. Very well put by you.

commented 12 years ago

Bob/PKB

MYCATSMOM: I hope that stuff up there makes sense. You actually do alot of algebra in your daily life without even thinking of it.
You pay $3 for 2 pounds of tomatoes; you want to know how much 1 pound costs. In algebra it is:
2X = $3.00 (X is the cost of one pound.
You know that 2 of that number is $3) You already know that 1 pound is $1.50 because you know that half of $3.00 is $1.50. You divided $3. by 2 to get the $1.50. That's algebra!

OR....You go bowling and your scores are 120, 147 and 153. What's your average?
You know you have to add the scores and divide by the number of games you bowled (3). SO in algebra, it would look like this:
(X + Y+ Z)/3 = A (for AVERAGE)
X = 120, Y = 147 and Z = 153.
(120 + 147 + 153)/3 = A.
Add 'em up. The total is 420.
420/3 = A
Divide by 3 (the number of games) and the average is 140.
140 = A

commented 12 years ago

mycatsmom

Karma: 393685

I flunked algebra in the 9th grade b/c our teacher never taught us anything. He only wrote the problems on the board, and then wrote the answers. He didn't teach us the mechanics of how to solve it. And he talked about a lot of other crap that didn't have anything to do with algebra. Then, the next day, he picked a row of students to go up to the board and write a problem on the board, and how they solved it. Boy, was that embarrasing when I had to do a problem in front of eveybody - - - - it was all greek to me. My brother had trouble with him too.

12 years ago. Rating: 2
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Bob/PKB

I got to do some subbing about ten years ago. One thing I learned really quickly was not to call on students to read or go to the board. Very embarrassing and humiliating. If a student wanted to help, that was one thing. No better way to turn someone off than to "pick" on him/her. I almost flunked algebra. It makes a lot more sense now, but I wouldn't want to sit in a classroom and have to produce every day. Teachers can make us or break us, can't they.

commented 12 years ago

mycatsmom

that's right, Bob /PKB. And Jr. high was hard enough with out me having to go up to the board and show everybody that I was as stupid as they thought I was.

commented 12 years ago

schubee