# i need some serious help with simplification :(

• Jul 19th 2010, 02:35 PM
jayleensmama
i need some serious help with simplification :(
hi im new here and i hope you can help me.. i need help with 3 parts to a math question that i have been struggling with all day.

a. x+2/3 - x + 5/2x

b. x+3/x-4 + 3x-1/5x-20

c. 3/x2 +7x +12 + 2/x2 - 2x - 15

and help would be greatly appreciated..
• Jul 19th 2010, 02:45 PM
bigwave
first you should use latex or more () these expressions could mean several things

assume the first one is, also are these supposed to = anything?

$\frac{x+2}{3} - \frac{x + 5}{2x}$
• Jul 19th 2010, 02:47 PM
skeeter
Quote:

Originally Posted by jayleensmama
hi im new here and i hope you can help me.. i need help with 3 parts to a math question that i have been struggling with all day.

a. (x+2)/3 - (x+5)/(2x)

b. (x+3)/(x-4) + (3x-1)/(5x-20)

c. 3/(x^2+7x+12) + 2/(x^2-2x-15)

and help would be greatly appreciated..

for starters, note the proper use of parentheses to make each expression clear.

to add fractions, you need a common denominator.

using (c) as an example ...

3/(x^2+7x+12) + 2/(x^2-2x-15) =

factor each denominator ...

3/[(x+3)(x+4)] + 2/[(x-5)(x+3)] =

note that the common denominator is (x+3)(x+4)(x-5)

3(x-5)/[(x+3)(x+4)(x-5)] + 2(x+4)/[(x-5)(x+3)(x+4)] =

(5x-7)/[(x+3)(x+4)(x-5)]
• Jul 19th 2010, 02:48 PM
jayleensmama
thats what it looks like on my paper but i have no idea how you put that like that on here..
• Jul 19th 2010, 02:57 PM
bigwave
see the latex tutorial in "latex help"

as for #a the common denominator is 6x multiply each term by this and cancel then combine terms.
do the same with the others as skeeter mentioned.

still need to see steps for this?

here is where the latex button is.