Question

1. x+1 2
---- - -----
x^2+5x-14 3x+21

2. x^2-49 x 2x-x^2
------- -------
x^2-9x+14 9x^3-3x^4

Answer 1

In the first case, you're subtracting two fractions, which happen to have different denominators. The very first thing to do here is to factor both given denominators and then to determine the least common denominator (LCD).

In the secon case, you're multiplying two fractions. Again, I'd suggest you start by factoring everything. Then cancel out any like factors. Then multiply.

Answer 2

@mathmale for the second one i got (x-7) (x+7) 2x(x)
---------- x ------
(x-7) (x+2) 3x^3 (3-x) but theres only one thing to factor

Answer 3

@DSS can you help? sorry for all the questions!

Answer 4

It's OK

Answer 5

thanks!! i had like 80 questions and there were a few i didnt get

Answer 6

x+1 2
---- - -----
x^2+5x-14 3x+21

denominators: (x+7)(x-2) 3(x+7)

Take care of the numerators now since the denominator will be 3(x+7)(x-2)

Answer 7

@xokatexo : regarding the 2nd problem: I agree with your factoring, except in the case where you typed 2x(x). Mind going back and checking that?

Answer 8

3(x+1) + -2((x-2) = 3x+3-2x+4 = x+7

Answer 9

how did that factor to be 1?

Answer 10

Are you asking me?

Answer 11

yeah

Answer 12

go up to my picture 5 above

Answer 13

thats just the original problem though

Answer 14

3(x+1)+-2(x-2) = 3x+3-2x+4 = x+7

Answer 15

ohh wait no i was talking about the 2nd problem

Answer 16

x+7 is the simplified numerator. I put it over the denominator of 3(x+7)(x-2)

Answer 17

i understand the first problem thank you you were very helpful

Answer 18

but i dont understand the second one

Answer 19

The x+7 cancels out in the numerator and denominator. Leaving 1 in the numerator

Answer 20

k

Answer 21

You have to factor lots.

first fraction (x+7)(x-7)/(x-7)(x+2)

Answer 22

yeah i got that

Answer 23

second fraction
x(2-x)/3x^3(3-x)

Answer 24

Now combine and multiply

Answer 25

Now multiply. Computer is dying...I'll be off for a minute

Answer 26

numerator (x-7)(2-x)

denominator (x+2)(3x^2)(3-x) doesn't simplify any further

Answer 27

sorry it took so long

Answer 28

thank you so much!! sorry it wouldnt let me send that before