## anonymous 5 years ago 4/x+12/x+3=-13

1. anonymous

$\frac{16}{x} + 3 = -13$ $\frac{16}{x} = -16$ -16 x = 16 x = -1

2. anonymous

no it' 4 over X and 12 over X+3 = -13

3. anonymous

ohh.... so $\frac{4}{x} + \frac{12}{x + 3} = -13$

4. anonymous

$\frac{4(x+3) + 12(x)}{x(x + 3)} = -13$ cross multiply 4(x+3)+12(x) = -13(x(x+3))

5. anonymous

4(x+3)+12(x) = -13(x(x+3)) 4x + 12 + 12x = -13x^2 -39x 13 x^2+55 x+12 = 0 (4 + x) (3 + 13 x) = 0 $x = -4, -\frac{3}{13}$

6. anonymous

yes that's correct simplyfing rational expressions I don't understand the last part How did you get (4+x) (3+13x)=0

7. anonymous

it's factoring i should have wrote (13x + 3)(x + 4) it might look better this way but I'm not sure how i can explain factoring. go to this site http://tutorial.math.lamar.edu/Classes/Alg/Factoring.aspx example 3 part e look it over

8. anonymous

Thanks for all yor help

9. anonymous

no problem sorry i can't explain the factoring, but the site is awesome good luck

10. anonymous

It's ok thanks agan I'll check it out