Stumped by this seemingly simple circuit. Why is the voltage across the current source 36 volts and not 24 volts? Please explain step by step if possible, **thanks**.

[![enter image description here](https://i.stack.imgur.com/gDx19.png)](https://i.stack.imgur.com/gDx19.png)

(I solved it with an MIT circuit solver and it said that the voltage across is 36v):
[![enter image description here](https://i.stack.imgur.com/Xv6gN.png)](https://i.stack.imgur.com/Xv6gN.png)