You have the following expression:
(5x - 6.9)(2x + 12.2)
use the distribution property in the previous factors:
(5x - 6.9)(2x + 12.2) =
5x(2x) + 5x(12.2) - 6.9(2x) - 6.9(12.2) =
10x² + 61x - 13.8x - 84.18 =
10x² + 47.2 - 84.18
Hence, the simplfied expression is 10x² + 47.2 - 84.18