```
Manipulate[
Module[{x1, x2, t, sol, eq1, eq2},
eq1 = x2'[t] == k2 x2[t] - k1 x1[t];
eq2 = x1'[t] == k3 x1[t];
sol = First@
DSolve[{eq1, eq2, x1[0] == x10, x2[0] == x20}, {x1[t], x2[t]}, t];
Plot[{x1[t] /. sol, x2[t] /. sol}, {t, 0, tMax}, Frame -> True,
FrameLabel -> {{"solution", None}, {"time", "My nice plot"}},
BaseStyle -> 12, GridLines -> Automatic,
GridLinesStyle -> LightGray,
PlotRange -> {Automatic, {0, Automatic}},
PlotLegends -> {"x1(t) bad Wolfs", "x2(t) poor Sheep"}]
],
{{k1, .1, "k1"}, .01, 1, .01, Appearance -> "Labeled", ImageSize -> Tiny},
{{k2, .2, "k2"}, .01, 1, .01, Appearance -> "Labeled", ImageSize -> Tiny},
{{k3, .3, "k3"}, .01, 1, .01, Appearance -> "Labeled", ImageSize -> Tiny},
Delimiter,
{{x10, 2, "x1(0)"}, 0, 10, .1, Appearance -> "Labeled", ImageSize -> Tiny},
{{x20, 50, "x2(0)"}, 0, 100, .1, Appearance -> "Labeled", ImageSize -> Tiny},
{{tMax,3,"time"},.1,50,.1, Appearance->"Labeled",ImageSize->Tiny},
Alignment -> Center, SynchronousUpdating -> True,
SynchronousInitialization -> True, FrameMargins -> 1,
ImageMargins -> 1, ControlPlacement -> Left
]
```

your equations are not clear. Assumed second one is

`x1'[t]==k3 x1[t]`

– Nasser – 2017-12-03T23:54:58.760Thanks for the feedback, this is fixed! – Ubermensch_010 – 2017-12-04T00:34:19.270