To simplify the expression, we first need to factor the numerator and denominator:

Numerator: 5x^2 - 9x + 45 = 5(x^2 - 1.8x + 9)

Denominator: (x - 5)(x + 3)

Now we can rewrite the expression:

(5(x^2 - 1.8x + 9)) / ((x - 5)(x + 3))

Next, we can simplify the expression:

(5(x - 3)(x - 3)) / ((x - 5)(x + 3))

At this stage, the expression cannot be further simplified.