標題:
有8絛數學唔識做(代數)(15分)
發問:
1. 5x+35=80 2. -5y+35=-80 3. 7x+45=122 4. 7y-45=-122 5.x+3=-4 6.x+14=-7 7.y+31=-9 8.x-7=-2 (要有過程和答案)
最佳解答:
1. 5x = 80 - 35 x = 45/5 x = 9 2. -5y = -80 - 35 y = -115/(-5) y = 23 3. 7x = 122 - 45 x = 77/7 x = 11 4. 7y = -122 + 45 y = -77/7 y = -11 5. x = -4 - 3 x = -7 6. x = -7 - 14 x = -21 7. y = -9 - 31 y = -40 8. x = -2 + 7 x = 5
其他解答:
1, 5x+35=80 5x=80-35 5x=45 x=9 2, -5y+35=-80 5y=80+35 5y=115 y=23 3, 7x+45=122 7x=122-45 7x=77 x=11 4, 7y-45=-122 7y=122-45 7y=77 y=11 5, x+3=-4 x= -4-3 x=-7 6, x+14=-7 x=-7-14 x=-21 7, y+31=-9 y=-9-31 y=-40 8, x-7=-2 x=-2+7 x=7-2 x=5|||||其實好易咋喎, 答你唔係問題, 只係.....總要自己學下呢~~ 吾~~ 俾少少hints你丫~ 你試下先將冇代數果d計左先, 即係例如 (1) 5x+35 = 80 你先諗下點樣將個 +35 簡化, +35 可以調去 80 果邊架, 由 + 變 -..... 咁你調左個35過去計完再 將 5x 簡化~ 就ok架喇~~ 2. -5y+35=-80 呢題又係先移走個 35 先, 之後兩邊都係 - 嘛, 咁咪可以約左佢, 咁5y 再簡化就ok~ 3. 7x+45=122 先移走個 45,(記住 + 變 -, - 變+ 呀)~~ 之後7x簡化~ 4. 7y-45=-122 先移個 -45, 再簡化 7y 5.x+3=-4 先移3, 就知道答案喇~ 6.x+14=-7 就咁移個14過去~ (本來+移過去就變-呀, 記住呵!) 就得到答案喇~ 7.y+31=-9 又係移個31過去, 就知道答案~ 8.x-7=-2 呢題要移 -7 呀, 本來 -7, 移過去 - 又要變 + 呀~~ 其實真係幫你做唔係問題, 只係真係自己試下做會好d~~ 可能你會覺得我多事, 不過真係為你好先咁做~ 2006-10-24 23:57:46 補充: 其實我都覺得大家咁詳細寫答案,係害左佢~因為相信呢位小朋友一定就咁抄哂d答案,唔會自己再諗下計下咁,到第時測驗考試都係唔識!|||||1. 5x+35=80 5x=80-35 x=45/5 x=9 2. -5y+35=-80 -5y=-80-35 y=-115/(-5) y=23 3. 7x+45=122 7x=122-45 x=77/7 x=11 4. 7y-45=-122 7y=-122+45 y=-77/7 y=-11 5.x+3=-4 x=-4-3 x=-7 6.x+14=-7 x=-7-14 x=-21 7.y+31=-9 y=-9-31 y=-40 8.x-7=-2 x=-2+7 x=5|||||1. 5x+35=80 5x=80-35 5x=45 x=45/5 x=9 2. -5y+35=-80 35+80=5y 115=5y y=115/5 y=23 3. 7x+45=122 7x=122-45 7x=77 x=77/7 x=11 4. 7y-45=-122 7y=45-122 7y=-77 y=-77/7 y=-11 5. x+3=-4 x=-4-3 x=-7 6. x+14=-7 x=-7-14 x=-21 7. y+31=-9 y=-9-31 y=-40 8. x-7=-2 x=-2+7 x=5|||||1. 5x = 80 - 35 5x = 45 x = 9 2. 5y = 35 + 80 5y = 115 y = 23 3. 7x = 122 - 45 7x = 77 x = 11 4. 7y = -122 + 45 7y = -77 y = -11 5. x = -4 - 3 x = -7 6. x = -7 - 14 x = -21 7. y - = 9 - 31 y = -40 8. x = -2 + 7 x = 5|||||1. 5x+35=80 5x=80-35 5x=45 x=9 2. -5y+35=-80 -5y=-80-35 -5y=-115 y=23 3. 7x+45=122 7x=122-45 7x=77 x=11 4. 7y-45=-122 7x=-122+45 7x=-77 x=-11 5.x+3=-4 x=-4-3 x=-7 6.x+14=-7 x=-7-14 x=-21 7.y+31=-9 y=-9-31 y=-40 8.x-7=-2 x=-2+7 x=5 下次自己做!!!!|||||咁簡單都要問...... 幫你 = 害左你 請各位吾好答佢 !!! 2006-10-24 23:54:31 補充: oh shit ................ post 遲左 !!!!|||||1. 5x+35=80 5x=80-35 5x=45 x=9 2. -5y+35=-80 -5y= -80-35 -5y= -115 5y=115 y=23 3. 7x+45=122 7x=122-45 7x=77 x=11 4. 7y-45=-122 7y=-122+45 7y= -77 y= -11 5.x+3=-4 x= -4-3 x= -7 6.x+14=-7 x= -7-14 x= -21 7.y+31=-9 y= -9-31 y= -40 8.x-7=-2 x= -2+7 x=5|||||1. 5x + 35 = 80 5x = 80-35 5x = 45 x = 45 / 5 x = 9 2. -5y+35=-80 80 +35 = 5y 115 = 5y y = 115/5 y = 23 3. 7x+45=122 7x = 122-45 7x = 77 x = 77/7 x =11 4. 7y-45=-122 7y = -122+45 7y = -77 y = -77/7 y = -11 5. x+3=-4 x = -4-3 x = -7 6.x+14=-7 x = -7-14 x = -21 7.y+31=-9 y = -9 - 31 y = - 40 8.x-7=-2 x = -2 + 7 x = 5
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