Question

Determine whether the polynomial is a difference of squares, if it is, factor it.

y2 – 9

Answer 1

y^2 is a perfect square (since y^2 is "y squared")

but is 9 a perfect square?

Answer 2

yes

Answer 3

so if 9 = x^2 then what must x be if x were a positive number?

Answer 4

in other words, what goes in the box?

\[\Large 9 = \square ^2\]