easy peasy
the fastest way is to pretend we have 1 big rectangle with 2 smaller rectangles cut out
see attachment
the big one is 12 by 7
the smaller ones are 5 by6 and 5 by 6
big-smaller=area
big=12*7=84
smaller=5*6+5*6=30+30=60
big-smaller=84-60=24
answer is 24 in²
first choice