55* 74-74*50+50*70-70*45+45*66-66*40+40*62-62*35=

1 СПОСОБ1) 55 * 74 = 4 070 ;2) 74 * 50 = 3 700 ;3) 50 * 70 = 3 500 ;4) 70 * 45 = 3 150 ;5) 45 * 66 = 2 970 ;6) 66 * 40 = 2 640 ;7) 40 * 62 = 2 480 ;8) 62 * 35 = 2 170 ;9) 4070 – 3700 +3500 – 3150 + 2970 – 2640 +2480 – 2170 = 370 + 350 + 330 + 310 = 1360.2 СПОСОБ55 * 74 – 74 * 50 + 50 * 70 – 70 * 45 + 45 * 66 -66 * 40 + 40 * 62 – 62 * 35 = = ( 55 * 74 – 74 * 50 ) + ( 50 * 70 – 70 * 45 ) + ( 45 * 66 - 66 * 40 ) + ( 40 * 62 – 62 * 35 ) = =74 * ( 55 - 50 ) + 70 * ( 50 - 45 ) + 66 *( 45 - 40 ) + 62 ( 40 -35 ) == 74 * 5 + 70 * 5 + 66 * 5 + 62 * 5 == 5 * ( 74 + 70 +66 + 62 ) = 5 * 272 = 1360.