Answer
$1$
Work Step by Step
To add two numbers with different signs, we find the difference between their absolute values, and give the sum the sign of the number with the greater absolute value:
$$-4+5=|5|-|-4|=(5-4)=1$$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.