Is that what they call Common Core? I’ve heard the term but didn’t know how it changed the method of teaching math.

Common core showed multiple ways that were intended to increase the understanding of how math works. This was one of the ways that was presented which wasn't how they taught it when I was a kid. There were at least two that I remember when my kiddo was doing common core:

• Double one of the numbers and add or subtract the difference between them (7 is two less than 9, so 9x9 then subtract 2)
• Take enough from the smaller number to reach 10 and add what is left (9+7 to 10+6)