How to analyse unseen prose (English lit AQA paper 2 Section A)

Okay, so I have looked at all of the assessment objectives and I know them. I understand that I have to be perceptive and have organisation; write about language, form and structure; talk about other interpretations; look at social and historical context etc. But as much as I've looked at mark schemes and the AOs I don't know how to go about answering the question. I haven't found any relevant examples and I really don't know how to start or what to say. For my homework I have to answer this question : "examine the view that Austen presents marriage only as an economic arrangement in this extract"

EXTRACT: http://filestore.aqa.org.uk/resources/english/AQA-7711-UE-3-PS.PDF

Could you please give me an paragraph example of how to answer the question? I don't know where to start or what to stay at all. Thank you.