math
posted by the last two .
5ã2x^3xã18xy^2 simplify as much as possible
(5+4ã2)(3+4ã10)multiple and simplify as much as possible

Assuming you meant
5√(2x^3)x√(18xy^2)
that is
5x√(2x)  3xy√(2x) = (5x3xy)√(2x)
(5+4√2)(3+4√10)
= 15 + 12√2 + 20√10 + 16√20
= 15 + 12√2 + 32√5 + 20√10