Hopefully this will show up bigger so people can see it but I'm unsure of how to do this question.

I have done questions similar to this, but not with angles at the two sides


The question on top is what I have done previous with this sort of question, the bottom is me trying to work out the answer for this question but I'm not too sure if the answer is right or if I have the right answer what it is?

Some help would be greatly appreciated