Question 37026
First you must factorize both equations

Eq1 x^2-3x-10=(x-5)(x+2)
Eq2 x^2-x-20=(x-5)(x+4)

Therefore:

(x^2 – 3x – 10)/ (x^2 – x – 20)=[(x-5)(x+2)]/[(x-5)(x+4)]

As you see both equation has a common factor (x-5),and finally, the result is
(x+2)/(x+4).

(x^2 – 3x – 10)/ (x^2 – x – 20)=(x+2)/(x+4)

If you need something more let me know.