## Pologirl19 simplify the sum d^2-9d+20 / d^2-3d-10 + d^2-2d-8 / d^2+4d-32 one year ago one year ago

1. Pologirl19

$\frac{ d^2 - 9d + 20 }{ d^2 - 3d -10 } + \frac{ d^2 - 2d - 8 }{ d^2 + 4d - 32 }$

2. Pologirl19

3. zepdrix

Ok looks like we have to do some factoring :) Hmm let's look at it piece by piece.$\large \frac{\color{orangered}{d^2-9d+20}}{\color{green}{d^2-3d-10}}+\frac{\color{royalblue}{d^2-2d-8}}{\color{purple}{d^2+4d-32}}$Let's look at the green portion first.

4. zepdrix

We want factors of -10, that add to form -3. Hmm let's try $$-10$$ and $$1$$. $$-10\cdot1=-10$$ ok good, but if we try to add them, $$-10+1\neq-3$$. Hmm ok those factors won't work. Can you think of any other factors of -10? :)

5. summer1980

$\frac{ (d-5)(d-4) }{ (d-5)(d+2)}+\frac{ (d-4)(d+2) }{ (d-4)(d+8)}=\frac{ d-4 }{ d+2}+\frac{ d+2 }{ d+8}$ i hope this helps