Answer:
D. difference of squares
Step-by-step explanation:
Both of the terms x^2 and 9 are squares, so their difference is the difference of squares. The factorization of that is a "special form" that can be usefully memorized.
a^2 -b^2 = (a -b)(a +b)
x^2 -9 = (x -3)(x +3)
Answer:
Arithmetic
Step-by-step explanation:

<em>We choose any values of x and calculate the value of y</em>

<h3>Answer: (-4, 1), (-1, 2), (2, 3).</h3>
The equation is
y = $10,000+ $225x
<em>$225 (6) + $10,000 = y</em>
<em>$1,350 + $10,000 = y</em>
<em>$11,350 = y</em>
He will have saved $11,350 dollars in six months.