I have been solving some past exam questions and I came across the following question. Let $r$ and $s$ two distinct lines in $\mathbb{R}P^2$, and let $X$ the space obtained contracting $r \cup s$ to a point in $\mathbb{R}P^2$. Say if $X$ is a topological manifold. I can not imagine what $X$ is, and i think this is my problem. Help would greatly be appreciated.
2026-05-06 07:55:52.1778054152
$\mathbb{R}P^2$ and its lines
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Contracting one line to a point gives a sphere. (Why?) Contracting two lines then is equivalent to contracting one loop on a sphere to a point. What do you think you'll get?