Write the interval notation corresponding to the set notation

{x | x < –7}

For the interval notation, ( and ) correspond to excluding the lower and upper limits. While [ and ] imply the inclusion of the lower and upper limits.

The two limits are separated by a comma.

Thus
[-5,8) is the same as {x|-5=<x<8}

So the correct answer would be:
(negative infinity, -7)

See also
http://www.jiskha.com/display.cgi?id=1243999516

Would this work as well to represent that answer? (-infintity symbol, -7)

Yes, definitely.

I would have put the infinity symbol if I could get it posted correctly.
Note also that negative infinity itself has been excluded from the interval because of the parenthesis instead of the square bracket.

Thanks for you help!

Hope you got your answer AND understood well the interval notation.

To write the interval notation corresponding to the set notation {x | x < -7}, we need to understand interval notation.

Interval notation uses parentheses and brackets to express intervals. Here are the symbols used in interval notation:

- Parentheses ( ) denote an open interval that does not include the endpoints.
- Square brackets [ ] represent a closed interval that includes the endpoints.
- Infinity (∞) represents values that continue indefinitely.

Now let's apply this to the set notation {x | x < -7}.

In this set notation, the condition is x < -7, which means it includes all values of x that are less than -7. However, since the symbol "<" does not include -7 itself, we will use parentheses to represent an open interval.

The interval notation corresponding to {x | x < -7} is (-∞, -7).