a, (37-17). (-5) +23 . (-13-17)
=20. (-5) +23. (-30)
= -100-690
= -790
b,(-57) . (67-34)-67.(34-57)
=(-57).33-67 .(-23)
= -1881 + 1541
= -340
a, ( 37 - 17 ) . ( -5 ) + 23 . ( -13 - 17 ) b, ( -57 ) . ( 67 - 34 ) - 67 . (34 -57 )
= 20 . ( -5 ) + 23 . 4 =-57 . 69 + 57 . 34 - 67 . 34 + 67 . 57
= -100 + (-690 ) = 57 . 34 - 67 . 34
= -790 = 34 . ( 57 - 67 )
= 34 . ( -10 )
= -340
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