Suppose the price of housing increases to 3, but the price of food stays at 10.
Rewrite Jane's budget constraint and draw it on a graph.
Now suppose the price of housing decreases to 1.
Rewrite her budget constraint again.
When the price of housing increases does her budget constraint become steeper or flatter?
When the price of housing decreases does her budget constraint become steeper or flatter?
What happens when the price of food increases or decreases, but the price of housing stays at 2?