Solving differential equation using Fourier Transform

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I have the following differential equation I need to solve:

$x'(t) + 2x(t) = u(t)$

So here's how I proceed:

$F^{-1} (x'(t)) + 2 F^{-1} (x(t)) =F^{-1} ( u(t))$

$2\pi if \hat{x}(f) + 2\hat{x}(f) = \frac{1}{2} \delta(f) + \frac{1}{2 \pi if } $

$\hat{x}(f) (2 + 2 i \pi f) = \frac{1}{2} \delta(f) + \frac{1}{2 \pi if }$

$\hat{x}(f) = \frac{\delta(f)}{2 (2 + 2 i \pi f)} + \frac{1}{2\pi i f (2 + 2 i \pi f)}$

So now:

$x(t) = F^{-1} (\frac{\delta(f)}{2 (2 + 2 i \pi f)}) + F^{-1}(\frac{1}{2\pi i f (2 + 2 i \pi f)})$

And that's how far I got. I don't know how to proceed.