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anonymous
 5 years ago
5x(3x+2)6 < 4X(2X5) +12
anonymous
 5 years ago
5x(3x+2)6 < 4X(2X5) +12

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Do you have any guesses on how to start this problem?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I multipy 5x 15+106< 4x 12x20+12, I am not good at all with algebra.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You were indeed correct to start off by distributing. But we have a couple minor errors with your distribution, however.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0When you multiply 5x times 3x, what do you get?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Actually, you get 15x^2. The x's multiply with each other. But the 5*3 was spot on.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Do you see how that works?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Do you see how that works?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Alright, now let's try to multiply the 5x and the +2 together.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.05x(3x+2)6 Hmm.. Not quite. Maybe you don't know where I am talking about. In the above phrase, will you take the 5x and multiply it with the 2 in the parenthesis?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Mm.. Not quite. Remember, the x is a variable, not the same as a multiplication symbol. 5x * 2 = 10x

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh, and by the way, * is the computer symbol for multiplication. And that's the reason why, we don't want to get confused about whether it's a letter x or an operation so we use *.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Great. So if you want to double (or multiply by two) your five X's, you now have 10 X's. Is that clear?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So on the left side we went from: 5x(3x+2)6 To: 15x^2 + 10x  6 Following? Now we'll want to do distribute on the right side: 4X(2X5) +12

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Cool, can you distribute on the right side then? 4X(2X5) +12

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Hmm.. Let's try this together. 4X(2X) Can you do this for me? Remember what I said above about multiply two Xs together.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Excellent, very very good. Now you left out one last part for the right side: 4X(2X5) +12 Can you do the 4x * 5?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm afraid not. 4x * 5 = 20x Pretend that an X is an item. Don't even bother calling it a variable. Now, I have 4 Xs. If I have 4 Xs and I multiply my Xs by negative five, how many Xs do I have?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Hmm.. Let's try something a little different. If I have 4 pennies and you said that you could multiply my pennies by five, by the end of it, how many pennies would I have?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Exactly. Now, pretend that my pennies were really just little X's all along. Not a letter, not a variable, a real X, something I could hold in my hands. I'll ask you the same question. If I have 4 X's in my hand and you said you could multiply my X's by 5, how many X's would I have?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Great, does that make it a little more clear? That is how you should approach these problems when multiplying X's. Just pretend they are just labels. :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yes it does, thank you!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So we had this: 5x(3x+2)6 < 4X(2X5) +12 And turned it into this: 15x^2 + 10x  6 < 20x^2  20x + 12 When we solve algebraically, we'll want everything that has that nasty X on the same side of the inequality. Do you know how you might accomplish that?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.015x2+10x6 < 20x220x+12 15x+6 20x12

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Afraid not. We'll want to do: 15x^2 + 10x  6 < 20x^2  20x + 12 +6 20x^2 +20x +6 To get: 15x^2 +10x  20x^2 + 20x < 18

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0From there we can combine like terms: The x^2s can combine. 15x^2  20x^2 = 5x^2 The X's can combine. 10x + 20x = 30x So we end up with: 5x^2 + 30x < 18.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You subtracted 2 on both sides to get the answer 18 and combined like terms 15x 20x and 5x and added 10+20 = 30.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I added six to both sides to get +18 on the right side. The rest is correct :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Now, are you familiar with the quadratic equation?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yes I understand somewhat, however I will continue to practice and study for a better understanding. Thank you so much for your help!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0It's no problem. I just wish I could be a little more clear, it's hard to do that with just text. Anyways, we'll use the quadratic equation, first we have to make the equation equal to 0: 5x^2 + 30x < 18 18 18 5x^2 + 30x 18 < 0 And then plug in the A, B, and C values into the quadratic equation: b plus/minus sqrt of b^2  4AC all divided by 2A  30 plus/minus sqrt 30^2  4*5*18, all divided by 2(5) = 16.905 and 133.09. Those are your values of X and those are the answers. Two of them.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I screwed up my math somewhere. The system is true when: 4.819 < X < 0.533

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0And that's the answer.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Okay thank you!!!! I am going to print out this information and study it and I will practice other problems. Thanks again!!!!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0No problem Sorry I couldn't be more clear.
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