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general maths algebra question help!!? (1 Viewer)

LouisaCar

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hey guys,
could someone please help me solve this algebraic equation ( I'D REALLY APPRECIATE IT !!!)

3p-2/5 - 2p+1/4 = 3

Thankss
 

deswa1

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Do you mean (3p-2)/5-(2p+1)/4=3? If so, multiply both sides by 20 to eliminate the fractions:
4(3p-2)-5(2p+1)=60
12p-8-10p-5=60
2p=73
p=73/2
 

deswa1

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Okay. What I'm guessing they mean is this:
Q. 3p -(2/5) -2p -(1/4) =3
p=3+0.4+0.25
p=3.65

The problem with this is that the answer is 10x bigger (probably typo) and the question requires -1/4 instead of +1/4 in your original question.
 

LouisaCar

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THANKYOU
No, in the book it did not have brackets
what I did wrong was write down 5 as a positive instead of a negative and ended up with 2p=63
I have another question then though... when a fraction has a negative in front of it e.g. like in this equation ---> -2p+1 / 4 , doesn't this make the whole fraction negative including the 4 at the bottom that you multiply the other fraction by :s
 

deswa1

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I don't totally get your question. A negative in front of a fraction makes the fraction negative. This means that either the numerator is negative or the denominator is negative but not both :

-(4/5)=(-4)/5=4/(-5) but DOES NOT equal (-4)/(-5)

Does that make sense?
 

LouisaCar

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Yes I understand, I just had a tutor one time that said that if there is a negative sign in front of a fraction it means the whole fraction is negative and i.e. - 4/5 = (-4)/(-5) :mad: arghhh!

Thanksss once again !!
 

deswa1

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No worries. If you need any other help, you can PM me :)
 

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