Prove: If a connected graph $K$ has $n$ vertices and $x$ edges with $x > n − 1$, will it contain a cycle?

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I'm new to graph theory and I'm trying to prove this problem, but I am not sure how to go about it.

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Let us assume it doesn't, so it's acyclic. So it is either a forest or a tree, which has $n-1$ edges. However it has at least $n$ edges, so it can't be neither. If it can't by an acyclic graph, it has to have a cycle, therefore it has a cycle

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Note that with each edge you add to the graph that does not generate a cycle, the number of connected components decreases by exactly one.