36 * 7 gives you the number of nails in the whole pounds
36 * 2/3 gives you the fraction part
7 * 36 = 252
2/3 * 36 = 24
Total nails = 252 + 24 = 276 nails
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)