Answer:
x-3
Explanation:

1) look at the top equation and factor:
Factors of -30: 10,-3 6,-5 15,-2 -3,10 -6,5 -15,2
Factors adding up to 7: 10,-3
So x^2+10x-3x-30
X(x+10) -3(x+10)
(x-3)(x+10)
2) bring in the denominator terms

(x+10)'s cancel each other out
And your left with (x-3)
Hope this helps!