express in form a+bi

(1+2sqrt3)(2-3sqrt-3)
so I came up with
2-3i sqrt3 + 4sqrt3 - 18i
Is that solution a+bi form

(1+2√3)(2 - 3√-3 )

=2 - 3√-3 + 4√3 - 6√-9
= 2 - 3√3i + 4√3 - 18i

you had that , but they probably want it this way

(2+4√3) - i(3√3+18)
or
(2+4√3) + (-3√3 - 18)i

where a = 2+4√3
b = -3√3 - 18