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Pre-Algebra
I wanna get a hard-start for next year where were going to be learning basic algebra.
We satrted at the end of last year and it was So over my head i got soo confused with just stuff like
x(-4)=7
I just made that up by the way adn would that be 11?
So i was wondering if anyone could be nice and make some hard problems I dont want my family to know because they'd make fun of me..
Thanks!
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Maybe give some free advice about: School?
ive been taking algebra for that past to years so ill see if i can help because i still have all my notes from this year.
Evaluate if x=3, y=6
1) xy
2)x+y-2
3) if x=7 then 50-3x=
4) If x=7 then 2x(squared)-5x+4=
------------------------------------------------
Simplify:
5.)11x=33
6.)2x+3x+4=-6
7.)-5-4x+17x=73
if your confused ill show you a step by step with one
3x+2=17
-ok first you have to try to get the x by itself so subtract 2 from both sides
-which gives you
3x=15 because the 2's cancel out on the left side which is what you want
next you divide the 3 from both sides
to get x by it self and after you get
x=5 as an answer.
some rules.
a negitive divided by a postive is a negtive
a negitive divided by a negitive is a positive
a positive divided by a negitive is a negitive
a positive divied bya positive is a positive
i was taught to remember it like this there can never be just one negitive in an equation, my tutor told me all negitives come in pairs.
so just someother little things to help
well after you finish them just message me and ill tell you if you got them correct.
hope i helped =]
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actually the equatoin x(-4)= 7 is not 11.
if it was, it would look like x+(-4)=7
with an addition sign
the correct answer is x = -1 3/7
other equations you could do are:
x(7)=28
2(x+5)=30
x-4+9-x=20
2(4-x)=5(3+x)
message me with the answers and ill tell you if you got them right or not!
happy math-ing
=]
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Algebra..i learned it this year. Its not so hard.
Usually in multiplication you use an X to symbol "multiply" but now we use variables (letters) somtimes instead of numbers (when we are trying to figuire out the letter) so we cant use X anymore. Now we use a dot �
There is the power stuff which is like
5³ would be 5�5�5 which would be (or five times five times five)
To work this out, we would set it up like this
5�5�5
^
25 � 5
^
125
I know that looks complicated. The ^ symbol means that we solved part of the equation, and brought it down to the nect line. So the 5�5 with a ^ under it and then a 25 means that 5 times five is 25
I have my summer paket with me now so ill give you some of the problems.
A number directly to a variable means to multiply.
So 2x would mean 2 times x
(Or 2�x)
If any of this is confusing please leave me a messege in my inbox. I dont know how to explain it because i dont know which way will make sence. Algebra is like that. My teacher explains it three different ways because different people understand it worded differently.
Can you try this one now? (X is traditionally used as a variable most often)
12x=48
Now, 12 and X are connected so we need to seperate them. To do this, we need to do the opposite of what is supposed to be done to X.
So 12 is supposed to be multiplyed by x, so we need to devide it by x. What we do to one side of the =, we need to do to the other so we devide 48 by 12 also.
Does that kind of make sence? What did you end up with?
It should have been x=4
If you didnt get that, please messege me with what you got and ill help you figuire it out.
Mostly, algebra is just re-writing things until the make sence. Like "the product of 9 and the number x is equaled to nine" isnt very easy to work out so we need to look at what we know. Fistly, see where it says "the product of nine and the number x"? Product is the answer when you multiply so we know to multiply. So we have
NINE TIMES X
******Or 9x*********
Thats the first part. Now, see where it says "is equaled to nine"? That simply means
****** =9 *******
so if you put it together, you get 9x=9
Now, do you remember from the equation before this when we devided? Were going to do that again. 9x devided by nine is x
And 9 devided by 9 is one
So x is equaled to one
a fairly difficult equation would be
9 ( - 2 x + 7 ) + 11 x
In this equation, your going to have to distribute. We know this because the 9 is directly next to the (), with no plus or minus sign interfering. So we need to multiply the 9 by everything in the perenthesis.
9 times -2 is -18
9 times x is 9x
9 times 7 is 63
Now we've got
- 18 + 9x + 63 + 11x
Do you see the 9x and the 11x?
They both have x in them so we are going to combine them by adding then together
9x+11x=20x
So now we've got
-18 + 20x + 63
Now see the -18 and the 63?
We are going to combine them because they both dont have variables attatched to them.
- 18 + 63 is the same thing as
63-18
And 63-18=45
20x + 45 is as far as it will go
There dosent have to always be an answer, this is good enough.
Now, lets say they tell you that x is 0.991
You would have to keep going
20(0.991) + 45
19.82 + 45
64.82 is your answer
BY THE WAY, I DID WRITE ALL OF THIS AND IT TOOK ME FOREVER.
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it would be eleven if the problem was set up as x-4=7.
But because you put parenthesis on the -4.. the equation would be -4*x=11. so x=11/(-4)
yah know?
try this problem..
x+7*92^2-(98+39)/29-22=12
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In your problem, x= -1.75. You find this by dividing -4 by 7(7/-4). The variable x is being multiplied by -4 to equal 7.
x*-4=7
You "undo" multiplication by dividing one of then numbers from both sides.
x*-4=7
-------------(division)
-4 -4
After you divide -4 from both sides, -4 is eliminated from the left side and 7 turns into -1.75
x=-1.75
And there's your answer. Here's a picture I made of the above, if it isn't clear enough for you:
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Try these examples:
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If that's not a permalink, navigate through these menus to reach it:
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Here is how you properly show your work on problems, and I've also put some more info on how to solve the problems:
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Sorry for my horrible handwriting.
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well i just so happen to have an algebra book.
its algebra one. so here are some problems.
2n-5=7
3+4x=-1
3b+7=-2
-10=-6+2y
5y-2=-2
0=3x-3
2z+4=-6
4x+9=1
3x+2=20
-b+5=-16
y/2+5=-12
7-3k=-14
1+m/4=-1
41=5-6h
1.3n-4=2.5
x/3-9=0
-t-4==-3
3.5+10m=7.32
7=-2x+7
14+h/5=2
just so ya know if theres something that looks like y/5 or h/4 those are fractions in the problem.
uhh yeah if you want anymore questions or have any specific questions you can ask me more. =)
hope this helps
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This site is great for what you want:
[[Link](Mouse over link to see full location)]
You can get practice problems, the lessons are explained, and everything.
The one you made up, no it wouldn't be 11. You'd distribute, so you'd have -4x=7. Then you'd divide by negative four on both sides, so you'd end up with x= -7/4. Remember PEMDAS, or the order of operations? Parentheses, Exponents, Multiply&Divide, Add&Subtract? Well, when you're simplifying expressions like 4x+3=15, you do it all in reverse. First you'd subtract 3 from both sides, THEN you'd divide.
If all that went over your head, don't worry. You haven't even taken Algebra yet. Teachers explain things different ways, so ask more than one if you're stuck. Mr. Smith won't get mad if you ask Mrs. Jones for help, they all work for the same department. Don't be afraid to ask for extra help, and ask a student to explain things to you. They think on the same level as you, if that makes sense...
Oh, and don't be ashamed of wanting to get a head start. Be proud that you care enough about your education! :)
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