Respuesta :

Answer:

no. 4

Step-by-step explanation:

=25x - 125/x^2 - 25

=25(x-5) / x^2 - 5^2

=25(x-5) / (x-5) (x+5) <use of formula a^2 - b^2=(a-b) (a+b)>

=25/x+5 <cut (x-5) on both side>