Second Order ODE using ode45

I'm trying to solve a problem where I have 2 second order ODE problems.

The first is used if x<=150: x'' = 9.8 – 0.00324 (x’)2 m/s2

the second is used if x>150: x'' = 31.23 – 0.00324 (x’)2 – 0.143x – 1.5/70 x’ m/s2

I need to plot x, x', and x'' (which I can figure out), but I'm stuck on how to create the ode45 function for my 2 equations.

Any help would be appreciated. Thanks.