Skye says that x^3 – a^3 = (x – a)(x^2 + ax + a^2) is a polynomial identity because when she substitutes 2 in for x and 3 in for a she gets –19 on both sides of the equation.

: Do you agree with Skye’s statement? Show your argument.

: How else could you prove if x^3 – a^3 = (x – a)(x^2 + ax + a^2) is a polynomial identity?