Linear Equation: (5/3x)-(5/2)=-(4/9)

crappiefisher26

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Joined
Jul 23, 2006
Messages
49
Ok heres the question. (5/3x)-(5/2)=-(4/9)

Here is how i understand how to figure it out. It asks me to solve for x, write answer as fraction and in simpilest form.

6(5/3x-5/2)=6(-4/9)

then i got
6(5/3x)-6(-5/2)=6(-4)

30x-30=-24

30x-30+30=-24

30x=-24

Then i divided both sides by 30 and got -(4/5) but that wasnt right.

heres another question that i asked my professor about. same type.

(9/8x)+(3/4)=(7/2)

8((9/8x)+(3/4))=8(7/2)

8(9/8x)+8(3/4)=8(7/2)

9x+2(3)=4(7) simplifies to 9x+6=28

then he got 9x+6-6=28-6

9x=22, then he divided both sides by 9 and got (22/9).

Im really confused. cause i did a couple and emailed him all my work and answers and they were wrong. So i dont know what to do anymore.
 

royhaas

Full Member
Joined
Dec 14, 2005
Messages
832
Re: Linear Equation

crappiefisher26 said:
Ok heres the question. (5/3x)-(5/2)=-(4/9)

Here is how i understand how to figure it out. It asks me to solve for x, write answer as fraction and in simpilest form.

6(5/3x-5/2)=6(-4/9)

then i got
6(5/3x)-6(-5/2)=6(-4)
Your next step should read \(\displaystyle 10x +15 = -8/3\).
 

stapel

Super Moderator
Staff member
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Feb 4, 2004
Messages
15,943
crappiefisher26 said:
(5/3x)-(5/2)=-(4/9)

6(5/3x-5/2)=6(-4/9)

6(5/3x)-6(-5/2)=6(-4)

30x-30=-24
What you posted would seem to indicate the following:

. . . . .\(\displaystyle \L \frac{5}{3x}\,-\,\frac{5}{2}\,=\,-\frac{4}{9}\)

But going from the third line (in the quote above) to the fourth seems to indicate that you meant the following:

. . . . .\(\displaystyle \L \frac{5}{3}\,x\,-\,\frac{5}{2}\,=\,-\frac{4}{9}\)

Is this latter guess correct? That is, did you mean "(5/3)x - 5/2 = -4/9"? Also, the only way the 6 could have multiplied (on the right-hand side) to give a "-4" would be if that fraction were a "-4/6" rather than "-4/9". Please confirm or correct.

Thank you.

Eliz.
 

crappiefisher26

New member
Joined
Jul 23, 2006
Messages
49
this is correct. But im all confused now on how to do it from start to finish.
Could ya write it out and reply back to me.
Thanks.
 

jonboy

Full Member
Joined
Jun 8, 2006
Messages
547
Given: \(\displaystyle \L \;\frac{5}{3}\,x\,-\,\frac{5}{2}\,=\,-\frac{4}{9}\)

Add \(\displaystyle \L \,\frac{5}{2}\): \(\displaystyle \;\L \frac{5}{3}\,x\,=\,\frac{37}{18}\)

Divide by \(\displaystyle \L \,\frac{5}{3}\): \(\displaystyle \L \;x\,=\,\frac{37}{30\)
 
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