1/6
.........................................
9+9=18,а9+8=17
7+7=14, а 7+6=13
5+5=10, а 6+5=11
8+8=16, а 7+8=15
81с² -36сm + 4m² = (9c)² - 2·9c·2m + (2m)² = (9c - 2m)²
5706*48:72-(2450021-368606):903+7558501=7 560 000
1)2450021-368606=<span>2081415
2)5706*48=</span><span>273 888
3)</span>273 888:72=3804
4)2081415:903=2305
5)3804-2305=1499
6)1499+7558501=<span>7 560 000
</span>