S = 60 × 40 - ( 10 × 20 ) = 2200
60 × 40 = 2400
10 × 20 = 200
40+60*2=160
10+30*2=60
160-60=100
* бұл көбейту
S = 60 × 40 - ( 10 × 20 ) = 2200
60 × 40 = 2400
10 × 20 = 200
40+60*2=160
10+30*2=60
160-60=100
* бұл көбейту