Respuesta :

Answer:

(x + 9)(x - 5)

Step-by-step explanation:

x^2 + 4x - 45

factorising by using middle term break method

=x^2 + (9 - 5)x - 45

=x^2 + 9x - 5x - 45

=x(x + 9) - 5(x + 9)

=(x + 9)(x - 5)