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anonymous
 5 years ago
12x3(2x+7)=45 could someone walk me through this
anonymous
 5 years ago
12x3(2x+7)=45 could someone walk me through this

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You want to try and get the x on one side and the anything else on the other.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So I would start with distributing the 3 through that quantity...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Okay, so we start off by distrubiting the '3' to the (2x+7). 3*2x = 6x; 3 * 7 = 21 This leaves us with: 12x 6x 21 = 45 We group like terms: ie. 12x6x = 6x; We're left with 6x21=45, so lets add 21 to both sides. 6x21+21 = 45+21 This simplifies to: 6x = 24; we now divide by 6 x = 4. Done!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.03(2x+4)=5(32x) mind helping me again

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0tlk to me like im a 5 yr old lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Without just giving you the answer, it's always best to try yourself. That's the way you learn. So we need to distribute again, i.e multiply the 3 through and the 5 through.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Not quite. I think you had the right process because you used it on the right side correct. You forgot to multiply the 4 by 3.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Minus 12 :) So 6x12=1510x

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0see this where i get confused when do i need to change signs

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ok since the first time you are multiplying by 3 anything positive becomes negative.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0when i need to change from addition to sub

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i understand that but like on a 2 or 3 step prob when do i change the operation

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm not quite sure what you're asking. I would need an example...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0im really pretty intelligent i promise....lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0let me find an example

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Math is not everyone's thing. I just happen to be good at it. :) Music, on the other hand, I only listen to it.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Here's a few more examples of "changing the sign". I'm not sure I understand what you're asking so maybe you will see the pattern yourself. 3(7x+2) = 21x+6  A positive * a positive is a positive. 3(3x+2) = 9x6  A negative number * a positive is a negative. 5(2x1) = 10x  5  A positive number * a negative is a negative. 7(8x4) = 56x + 28  The first part is a negative * a positive = negative, but the second is a negative times a negative which is a positive. Can you try simplifying: 3(4x+7) = ??? for me?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yep! If it helps you to think of it as "Twelve x plus negative 21" then by all means leave it like that.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0As for the problem you posted above, first, let's simplify the left side by adding like terms. Then try adding something to both sides to get the x's on one side. Then add another something to get the "numbers" on the other side. Then divide by the number in front of the x to get your final answer.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.010x+9=3x+11 or 13x=20 cani combine both sides of the = sign at once?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0wait i just read what u wrote

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.06x+94x=3x+11 5x+9=11?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You can if you can keep track in it  with no offense met, I'd practice doing them individually for at least a week of classes. When you've got it down pat feel free to add on steps in your head. Eventually you'll reach a point where you can solve 6x+94x=3x+11 all in your head. You made a mistake in your answer though: Left hand side first: 6x+94x = 2x + 9; You added 4x in an attempt to kill the 4x, but if you're going to do that you must do that to both sides. It is far easier just to do "6x4x = 2x" Now the left side: Oh wait! It's already done! "2x+9" So we have 2x+9 = 3x +11; Subtract 2x from each side > 2x+92x = 3x2x+11 > 9 = x+11 Now lets subtract 11 from each side leaving: 2 = x; You can then check the answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Are you able to follow what I did? If you'd like I can give another example, but can you explain your thought process for me as you solve it?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Here's a problem I just made up if you'd like to try again: 5(3x+1) = 16x3

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Make sure to distrubute the "5" to everything in the parantheses.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so when one distrubutes you take the number outside of the parentheses and multiply it by each of the (inside terms). so you are doing: 5 * 3x; AND 5 * 1; so we have 15x 5 (or in your preffered notation: 15x + 5)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0We can come back to distrubution later if you'd like: 15x + 5 = 16x + 3 is where we can pick this up again. Do this out but tell me in words what you're doing as well please. I want to see what you're thinking haha. Cheers for sticking with this btw.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0then we combine the x's together so mobve the smaller x to both sides?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0trust me id rather b watching family guy,,,lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yep. So yeah, add the Opposite of the smaller x value to both sides.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.015x+5=16x+3 15x+5=15x+3 x=5=1x+3?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Also, I was asleep when making this example: The end result will be a fraction, my mistake.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Errr, okay, so explaint to me how you went from: 15x+5=16x+3 to 15x+5=15x+3

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0As a reminder, our first goal is to get rid of the x's from the left hand side. The way we do this is by adding the opposite of them to it. Anything + the opposite of anything = 0; Anything + Anything = 0.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0(and when we add anything (completely new) to one side, we must do it to the other).

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.015x+5=16x+3 15x=15=16x+3....so 20=16x+3...not done but thats how i do the first side right

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0u with me or u fall asleep again

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm not sure what you did there? Both sides are (by themselves) as simplified as you can get them without adding completely new things to the equation. Let's do this: 3x+2 = 4x+1 Each side is as simplified as possible: Let's get the x's over to the right. If I add 3x to both sides (which is the opposite of the the left hand side term), we get: 3x3x+2 = 4x+13x > 3 = 4x+1. Now using this example, try doing 15x + 5=16x + 3 again. Also, remember you can not add a variable, the "x's" to the constants "the numbers".

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Now using this example as a refrence, try doing* (correction to the above)
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