You can put this solution on YOUR website!
You can just use FOIL to multiply these. Or, if you notice, this expression fits the left side of pattern: , with "a" being and "b" being . I like using the patterns when possible. So, according to the pattern, your expression will work out to be:
which simplifies as follows:
9*7 - 4*6
63 - 24
39
Note: If you use FOIL you should get exactly the same answer.