6(83-10)
(50+14)÷2
(2+3)(6-2)
6(83-10) =6×83 - 6×10
= 242 - 215
(50+14)÷2
= 502+142
= 5+7
(2+3)(6-2) = 2×6+2×(-2)+3×6+3×(-2)
= 23-22+32-23
= 2
【練習】
7(2-3)
14-37
(22+62)÷2
11+6
(2+5)(3-1)
6-2+15-5
10(15+42)
56+85
(12-15)÷3
2-5
(7+3)(21-3)
43