题目
计算或解方程:
(1)
(2)
(3)
(4)
答案: 解: (−60)×(34+56) = (−60)×34+(−60)×56 = −45−50 =-95
解: (−14)−(−12) = −14+12 = −14+24 = 14
解: 2a2−12(ab+a2)−8ab = 2a2−12ab−12a2−8ab = 32a2−172ab
解: x−74−5x+83=1 , 去分母得: 3(x−7)−4(5x+8)=12 , 去括号得: 3x−21−20x−32=12 , 移项合并得: −17x=65 , 系数化为1得: x=−6517