1. ## Complex fractions

Can someone please help me with these math problems and explain them? I don't know what to do.

2x-18
divided by
x squared - 16

w squared + 5w
divided by w squared - 25

y squared + 8y +15
divided by m squared - m - 42

2. I'm going to assume you have to simply the expressions.

1. $\frac{2x - 18}{x^2 - 16}$
Take common factor in the numerator. Try to factor the denominator and then cancel.

2. $\frac{w^2 + 5w}{w^2 - 25}$
Again, common factor numerator, factor the denominator and cancel.

3. $\frac{y^2 + 8y + 15}{m^2 - m - 42}$
I'm not sure what you need to do here apart from just factor both the numerator and denominator.

3. Originally Posted by Chop Suey
I'm going to assume you have to simply the expressions.
Originally Posted by Chop Suey

1. $\frac{2x - 18}{x^2 - 16}$
Take common factor in the numerator. Try to factor the denominator and then cancel.

2. $\frac{w^2 + 5w}{w^2 - 25}$
Again, common factor numerator, factor the denominator and cancel.

3. $\frac{y^2 + 8y + 15}{m^2 - m - 42}$
I'm not sure what you need to do here apart from just factor both the numerator and denominator.

$\frac{2x-18}{x^-16}$

[tex]\frac{2x-18} factors to 2 (x+19)

x^2 -16 factors (x+4) (x-4)

2(x+9)

2 times (-9) = -18

x= 2

[tex]\frac{w^2 + sw}{w^2 -25)

(x+5) (x-5)

crossed out w+ 5 on the top and the bottom and I'm left with w divided by w-5

4. Originally Posted by Laura901

$\frac{2x-18}{x^-16}$

[tex]\frac{2x-18} factors to 2 (x+19)

x^2 -16 factors (x+4) (x-4)

2(x+9)

2 times (-9) = -18

x= 2
You cannot solve for $x$ as the equation is not equated to anything (ie. constant). Also, you are not given a value for $x$ which you could substitute.

Also, $2x-18 = 2(x-9)$.

Originally Posted by Laura901
[tex]\frac{w^2 + sw}{w^2 -25)

(x+5) (x-5)

crossed out w+ 5 on the top and the bottom and I'm left with w divided by w-5
This is correct.