35*17-35*16+65*99-65*98=
35*17=595
35*16=560
65*99=6435
65*98=6370
595-560=35
35+6435=6470
6470-6370=100
23*(79+21)-(23*(123-23))=23×100+23×100=23×(100+100)=23×200=4600
35*17-35*16+65*99-65*98=
35*17=595
35*16=560
65*99=6435
65*98=6370
595-560=35
35+6435=6470
6470-6370=100
23*(79+21)-(23*(123-23))=23×100+23×100=23×(100+100)=23×200=4600
