Simplify the rational expression: x−5 /x 2 −x−20

A. x−4
B. x+4
C. x 2 −15
D 1 /x+4

D

x ^ 2 - x - 20 =( x + 4 ) ( x + 5 )

( x - 5 ) / ( x ^ 2 - x - 20 )=

( x - 5 ) / [ ( x + 4 ) ( x + 5 ) ] =

1 / ( x + 4 )

Your answer is correct