Question

1. $5x^2 - 70x + 225$

Explanation:

Step1: Factor out GCF (5)

$5(x^2 - 14x + 45)$

Step2: Factor quadratic trinomial

Find two numbers that multiply to $45$ and add to $-14$: $-9$ and $-5$.
$5(x - 9)(x - 5)$

Answer:

$5(x - 5)(x - 9)$