We want all x's on one side, all the terms in t on the other.


Divide both sides by `(x + 3)` and multiply both sides by `dt`:


Next, divide both sides by t.


Integrate both sides.


Important: dx and dt must be on top of the fraction (i.e. in the numerator).


Take "e to power of both sides":


(We let `e^C=K`, constant)

So `x = Kt - 3`.

Typical solution and graph

We let `K = 7`, for illustration):

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Typical solution graph `x=7t-3`.

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