#### Mizuki

##### New member
Yes, I'm back. These things aren't being as fully explained as they were back in middle school; these are the types of problems I'm not getting today:

1) Simplify: 3 p^2 x^4 y p^5 x x y y^2
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My answer: 3 p^7 x^6 y^4 ?

2) Simplify by adding like terms: xyp^2 - 4p^2xy + 5xp^2y - 7yxp^2
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Is this right so far?

3) Factor Greatest common factor: 6 x^2 y^2 m - 14 x y^5 m^2 +24 x^10 y^6 m^4
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My answer: I honestly have no idea how to do GCF this way with exponents!

Any help would be greatly appreciated. Thank you!
_______________________________
Thank you Stapel. XD

#### Denis

##### Senior Member
Mizuki said:
1) Simplify: 3 p^2 x^4 y p^5 x x y y^2
My answer: 3 p^7 x^6 y^4 ?
Correct; good job :idea:

Mizuki said:
2) Simplify by adding like terms: xyp^2 - 4p^2xy + 5xp^2y - 7yxp^2
Is this right so far?
ALWAYS start by rearranging (alpha order of variables is easiest):

p^2 x y - 4 p^2 x y + 5 p^2 x y - 7 p^2 x y : quite clear now, right?

6 p^2 x y - 11 p^2 x y

-5 p^2 x y : all ok with you?

Mizuki said:
3) Factor Greatest common factor: 6 x^2 y^2 m - 14 x y^5 m^2 +24 x^10 y^6 m^4
Rearrange :idea: :

6 m x^2 y^2 - 14 m^2 x y^5 + 24 m^4 x^10 y^6

Now easy to see that highest factor applicable to all 3 terms is: 2 m x y^2 ; so:

2 m x y^2(3 x - 7 m y^3 + 12 m^3 x^9 y^4) : follow that ?

#### Mizuki

##### New member
Mizuki said:
3) Factor Greatest common factor: 6 x^2 y^2 m - 14 x y^5 m^2 +24 x^10 y^6 m^4
Rearrange :idea: :

6 m x^2 y^2 - 14 m^2 x y^5 + 24 m^4 x^10 y^6

Now easy to see that highest factor applicable to all 3 terms is: 2 m x y^2 ; so:

2 m x y^2(3 x - 7 m y^3 + 12 m^3 x^9 y^4) : follow that ?[/quote]

I finally get the adding like terms thing, thank you, but I"m still really fuzzy on the greatest common factor, so you see what number is divisible into all three whole numbers and then see what exponent goes into all the exponential variables? How did you get m^2 though? there were only 2 out of 3... ._.;;;

#### Denis

##### Senior Member
Mizuki said:
[ How did you get m^2 though? there were only 2 out of 3... ._.;;;
Not sure what you're asking, Mizuki; there is no m^2 in my solution:
2 m x y^2 (3 x - 7 m y^3 + 12 m^3 x^9 y^4)

#### Mizuki

##### New member
Denis said:
Mizuki said:
[ How did you get m^2 though? there were only 2 out of 3... ._.;;;
Not sure what you're asking, Mizuki; there is no m^2 in my solution:
2 m x y^2 (3 x - 7 m y^3 + 12 m^3 x^9 y^4)

I swear on betty june unger it was there a second ago... o__o;;;

Heh, Now the only thing I dont understand is the two expressions in the parenthesis, can you explain that?

#### Denis

##### Senior Member
Mizuki said:
[
Heh, Now the only thing I dont understand is the two expressions in the parenthesis, can you explain that?
Huh? I see 3 in there:
(3 x - 7 m y^3 + 12 m^3 x^9 y^4)
3x
7my^3
12m^3x^9y^4

plus what do you mean by "I don't understand"?

#### Mizuki

##### New member
Denis said:
Mizuki said:
[
Heh, Now the only thing I dont understand is the two expressions in the parenthesis, can you explain that?
Huh? I see 3 in there:
(3 x - 7 m y^3 + 12 m^3 x^9 y^4)
3x
7my^3
12m^3x^9y^4

plus what do you mean by "I don't understand"?
How did they get there, like how do you find out what to put in the parenthesis?

also, how would I do the problem "2/5 of what number is 40?" Just turn 2/5 into a decimal? Or... ._.

#### Mizuki

##### New member
Ugh, now that I think of it, i've been doing all those problems incorrectly... When it asks "What fraction of 60 is 48" That's the same as "What percent of 60 is blah blah" right..? Or is it saying fraction because the missing blank is part of the fraction, and not the percent fraction side

__is___ x _____
of 100

I think that's right... any help denis?

#### Denis

##### Senior Member
Mizuki said:
How did they get there, like how do you find out what to put in the parenthesis?

also, how would I do the problem "2/5 of what number is 40?" Just turn 2/5 into a decimal? Or... ._.
Simple example:
6x^2 + 4x
LCD is 2x, so:
2x(3x + 2)

2x times 3x = 6x^2
2x times 2 = 4x

......................................................................................

n = number
(2/5)n = 40
2n / 5 = 40
2n = 200
n = 200/2 = 100 ; 2/5 times 100 = 40 :idea: