two /24's and only one gateway - is routing still possible?

[fbsdmail at dnswatch.com]

Greetings,
 I've been trying to figure an ideal solution to this for some time,
and thought I'd post the question here to see if anyone else is working
with this situation.
Here's my scenario;
I have a /24 with a prefix of 168.103.150.xxx with a gateway on this prefix
(DSLmodem).
I also have a /24 with a prefix of 75.160.109.xxx
My question(s) is/are:
1) is it possible to route both of these across the same GW?
2) if answer to 1) == NO, what might I do?

Thank you for all your time and consideration.

--Chris

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