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pilot94
Oct 13, 2008, 04:24 PM
I need help. I have a major 9th grade algebra test tomorrow.I need help solving for example:
2/3n-6=12
how do I solve for "n"?

3x+41 = -5x-7
how do I solve for x?

9+4(3X+1)=11
how do I solve for x?

Bural21
Oct 18, 2008, 09:20 PM
Example:

N - 10 x 2 + 6 = 20

First, subtract 6 from both sides:

N - 10 x 2 + 6 = 20

The six cancels out on one side, and the other side you're left with 14:

N - 10 x 2 = 14

Now, divide both sides by 2:

N - 10 x 2 = 14

The two's cancel out on the equation and you're left with 7:

N - 10 = 7

Now, add 10 to both sides.

N - 10 = 7

The ten's cancel out. You're now left with N = 17, which is the answer to the equation. Double check:

N - 10 x 2 + 6 = 20

Replace N with 17:

17 - 10 x 2 + 6 = 20

7 x 2 + 6 = 20

14 + 6 = 20

20 = 20

And there you are, good luck!

undeadboy999
Oct 22, 2008, 07:14 PM
2/3n-6=12

all right multiply the whole equation by 3 when you do this the three cancles out so your answer would look like this

2n-18=36

then you add 18 to 36 then you should get

2n=18

then divide 2n and 18 by 2 to get your answer

n=9

undeadboy999
Oct 22, 2008, 07:23 PM
3x+41=-5x-7

OK first add 5x to both sides which cancles out -5x so you should get

8x+41=-7

then you subtrct 41 from both sides which cancles out +41 so you should get

8x=-48

then you divide both sides by 8 you should get

x=-6

:D

undeadboy999
Oct 22, 2008, 07:31 PM
9+4(3x+1)=11

first you distribute to get rid of parenthasese so u get

9+12x+4=11

then you combine like terms to get

13+12x=11

then you subtract both sides by 13 so you get

12x=-2

so then you divide both sides by 12 so you get

x=0.166

chellyboo
Oct 30, 2008, 03:27 PM
hello can anybody help me on my math homework? Please[

chellyboo
Oct 30, 2008, 03:29 PM
Can somebody help me I don't know what I'm doing

ltruel4128
Nov 8, 2008, 03:12 PM
how do you solve -4x-6-3x=5

jakester
Nov 10, 2008, 10:36 AM
undeadboy, this is the only one that was incorrect. N should be equal to 27.

n - 9 = 18

n = 18 + 9

n = 27

2/3(27) - 6 = 12

millioner077
Sep 16, 2009, 05:46 PM
3x+41=-5x-7
3x+5x=-41-7
8x/8 = -48/8

x=6
so answer is 6

Unknown008
Sep 17, 2009, 07:44 AM
Hello millioner077. This thread is nearly six months old... I doubt if the OP is still here.

Bobbyflay
Sep 29, 2009, 09:02 PM
This is basic 1 step equation

say I have 2x + 1/3 = 5x

I first subtract 2x from both sides and making it

1/3 = 3x

Next I want to get rid of the 1/3 so I multipy by its reciprocal and this is how it shows 1/3 * 3/1 = cancels and = 1

So next you do that to the other side so 3x*3/1 =

X=9

____________________________________


2 step equation:

5X - 31 = 9x + 12

First get rid of the -31 by adding to both sides. -31 + 31 = cancels out. 12+ 31 = 43.

5X = 9x + 43

Now its time to get rid of the 9X to make it even for both sides. Subtract nine on both sides. 9x - 9X cancels out.

Leaving you with.

-4X = 43 Now time to divide - * - = +

X = -10.75 or -10 3/4

Unknown008
Sep 30, 2009, 06:47 AM
Bobbyflay, did you even read the previous posts?

sri340
Oct 5, 2009, 12:26 PM
A cave contains 2 brown bats and 3 gray bats. The bats fly out of the cave one at a time. What is the probability that the fourth bat to fly out of the cave is gray? Express your answer
as a common fraction.

Unknown008
Oct 6, 2009, 01:10 AM
A cave contains 2 brown bats and 3 gray bats. The bats fly out of the cave one at a time. What is the probability that the fourth bat to fly out of the cave is gray? Express your answer
as a common fraction.

The easiest way to to make a probability tree.
25258
Here is that one, listing all the possible outcomes for the first four bats. [Sorry it's so huge :o]

1. You can have either brown or black (from left to right), so, probability of having brown = 2/5 and that of grey is 3/5
2. Following each kind of possibility, the probability changes accordingly. For example, if a brown bat was the first one, (going though the upper branch), you have 1 brown left and 3 greys, with total of 4. So, P(brown) = 1/4 and P(grey) = 3/4, etc.
3. When all of one colour has gone out, only one remains. This happens if the two browns go first, only grey remain.
4. The probability of an event is given by multiplying each probability assigned to each branch you followed. For example, if you have b, b, g, g (b=brown, g=grey) the probability is 2/5 * 1/4 * 1 * 1 = 1/10
5. For your answer, find all the outcomes where the 4th bat is grey, and add the probabilities up, because it is either one, or the other.

If you have questions, feel free to ask. I know that it's quite difficult to understand this if it is the first time.