Differential Equations

$y=4-c e^{-\frac{(x+2)^2}{2}}$

$y=8+c e^{-\frac{x^2}{2}-2 x}$

$y=c e^{-(x+2)^2}+x$

$y+2 x=c e^{-\frac{x}{2}-2 x}$