As you have asked this question about the drain piping, I assume the slow draining condition has always been the case rather than something that just started.
But if this is just a recent occurrence, then is the slow draining from both sinks or just one side?
Is there a vent up to the vent stack inside the wall above those two connections? If not, those become S-traps which are illegal and can be prone to slow draining.
You could try plunging each side but that may not correct your problem.
After I used the plunger and if it doesn’t clear the problem, I’d use a 3/8” drain cable about 50’ long to cable the drain with.
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