Then take the a<sup>3</sup>b<sup>3</sup>c<sup>3</sup> through onto each of the three terms inside the parentheses, and then combine the exponents, where possible. For instance:
. . . . .x(x<sup>2</sup> + xy) = x(x<sup>2</sup>) + x(xy) = x<sup>3</sup> + x<sup>2</sup>y
There's nothing more you can do.
Eliz.