Question 337477
2/(X+4) + 1 = 12/(X^2+9X+20)

1={12/{(X+5)(X+4)} *(X+4)/2]

1=[{12  (X+4) }/{2(X+4)(X+5)}]    …  

(X+4) IS CANCEL AND 12/2 IS 6

1*(X+5)=[6(1/(X+5))  *(X+5)]    MULTIPLY THE INVERSE

1*(X+5) = 6  SUBTRACT BOTH SIDES WITH 5

X+5-5 = 6-5

X=1