標題:
2題數學題THX F.1
發問:
解下列方程 NO.1 4(2b+5)=13–5(9+b) NO.2 21-4b=11b–[3(10b–7)+45] 要步驟. 無限THX
最佳解答:
1. 4(2b+5)=13–5(9+b) 4(2b+5)=13–5(9+b) 8b+20=13-45-5b 8b+5b=13-45-20 13b=-52 b=-4 2. 21-4b=11b–[3(10b–7)+45] 21-4b=11b–[3(10b–7)+45] 21-4b=11b-(30b-21)+4 5 21-4b=11b-30b+21+45 21-21-45=11b-30b+4b -45=-15b 15b=45 b= 3
此文章來自奇摩知識+如有不便請留言告知
其他解答:
NO.1 4(2b)+4(5)=13-5(9)+5(b) 8b+20=13-45+5b 8b+20-20=13-45+5b-20 8b= -52+5b 8b-5b=-52+5b-5b 3b=-52 3b/3=-52/3 b=-52/3 NO.2 21-4b=11b-[3(10b–7)+45] 21-4b=11b-[3(10b)–3(7)+45] 21-4b=11b-(30b-21+45) 21-4b=11b-(30b+24) 21-4b=11b-30b-24 21-4b=-19b-24 21-4b+24=-19b-24+24 45-4b+4b=-19b+4b 45=-15b -15b=45 -15b/-15=45/-15 b=-3|||||1. 4(2b+5)=13–5(9+b) 8b + 20 = 13 - 45 - 5b 8b + 5b = 13 - 45 - 20 13b = -52 b = -4 2. 21-4b=11b–[3(10b–7)+45] 21 - 4b = 11b - [30b - 21 + 45] 21 - 4b = 11b - 30b +24 -4b - 11b + 30b = 24 - 21 15b = 3 b = 3/15 = 1/5 2007-10-10 16:23:36 補充: 第2題錯左....2.21-4b=11b–[3(10b–7)+45]21 - 4b = 11b - [30b - 21 + 45]21 - 4b = 11b - [30b +24]21 - 4b = 11b - 30b -24-4b - 11b + 30b = -24 - 2115b = -45b = -3|||||1)) 4(2b+5)=13–5(9+b) 8b+20=13-45-5b 8b+5b=13-45-20 13b=-52 b=-4 2)) 21-4b=11b–[3(10b–7)+45] 21-4b=11b-(30b-21)+45 21-4b=11b-30b+21+45 21-21-45=11b-30b+4b -45=-23b 23b=45 b=45/23|||||no.1 8b+20=72+8b 8b+8b=20+72 16b=92 no.2 21-4b=11b-(30b-21+45) 21-4b=11b-30b+24 21-4b=-19b+24 -23b=45|||||1.4(2b+5)=135(9+b) 8b+5=13-45+5b 8b+5=–32+5b 3b=-37 b=-12 1/3 2.21-4b=11b–[3(10b–7)+45] 21-4b=11b-(30b-7+45) 21-4b=-19b-38 59=23b b=2 13/23|||||1. 4(2b+5)=13–5(9+b) 8b+20=13-45-5b 8b+5b=13-45-20 13b=-52 b=-4 2. 21-4b=11b–[3(10b–7)+45] 21-4b=11b-(30b-21)+45 21-4b=11b-30b+21+45 21-21-45=11b-30b+4b -45=-23b 23b=45 b=45/23
留言列表