The coordinated of A would be 1,1.
Instead of going through the trouble of mentally moving the entire thing, just focus on the one you need to know the answer to, aka A.
Midpoint=12.5 let me know if this helps
The steps are shown here.
1) Factoring
2) Completing the square
3) Quadratic Formula
4) Graphing
So basically the answer would either be 5 or -5.
It’s just the same as if there were no decimal point. but if there isn’t a number in the quotient on the left of the decimal like #15, then you just place a 0 and continue to the next dividend which is 50.