How is this PC able to get online?

So, dumb question. I have a PC that's on my VLAN1 (don't kill me plz.) Info as is:

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VLAN1:

IP: 10.0.0.126 255.255.255.128

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PC: (statically set)

IP: 10.0.0.100

Subnet: 255.0.0.0

G/W: 10.0.1.126

​

Now I'm wanting to say that the reason it's online is because the subnet mask of the PC overlaps the whole 10.x.x.x subnet. But if the gateway is statically set wrong, how does the PC know to use the correct gateway; 10.0.0.126?