(x + 3)(x^2 – 2x + 7)

Answer 1

=x(x^2 – 2x + 7) +3(x^2 – 2x + 7)
distributive property

Answer 2

x(x^2 – 2x + 7)+3(x^2 – 2x + 7)
= x^3-2x^2+7x + 3x^2-6x+21
= x^3-2x^2+3x^2+7x-6x+21
= x^3+x^2+x+21 ---- this is the answer