Answer: [tex](-\infty, 7)[/tex]
You can write this as (-infinity, 7) if you aren't able to use the infinity symbol.
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Explanation:
Think of x < 7 as writing [tex]-\infty < x < 7[/tex]
So x is between negative infinity and 7, excluding both endpoints.
To write [tex]-\infty < x < 7[/tex] in interval notation, we write [tex](-\infty, 7)[/tex]
The curved parenthesis tell us to exclude the endpoint.
