Answer:
b=1
Step-by-step explanation:
9 (b + 7)= 72
9b + 63= 72
9b=9
unless you want the value when you plug the b back in with out solving then its 9
Input into your calculator to verify
See below.
the one on the left area is 104
the one on the right area is 19.5
80
probably would be the answer