Negative numbers: +/−

For a negative number, use the +/- key, not the - key. Type 42 and press . Press , then type 5. Press , type 120, and press . The value of $\displaystyle 42 \times (-5) + 120$ is −90.. It is also possible to type 5 first and then press +/-.

▶ Watch this step in the video (12:08)