Salsa + Mambo ?
Oh yes, you can combine the 2 dances even though they are two different dance.
For example; you can combine Swing with Jive. They are two different dance which branched off from the same root (jitterbugs or lindy.)
So for, Salsa branched off from Mambo, and then got mixed with or borrowed from other styles.
(like from Hustle, Swing, Cha Cha, Samba, Merengue, and Rumba.)
The more dances you LEARN and the more dancing you DO, you'll find that dance patterns can be inter-changed, mixed, or crossed-over.
From my own experience, I find it's more enjoyable (to dance) combining Merengue with Hustle.
Dancingly
Kato