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caw123456二星初級會員
2011-11-28 18:54#1
1. 8分之5(3-x)減2分之x加3 =0
2, 3分之t加1=6分之5t減1 加0.6
3, 5分之2y減1加4分之1加y=1減2分之1減y
快,要交功課!thanks!
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雪子秀版主
2011-11-30 12:01#2
1) [5(3-x)/8] - [4(x+3)/8] = 0
15-5x-4x-12 = 0
-9x = -3
x = 1/3
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2) [10(t+1)/30] = [5(5t-1)/30] + [18/30]
10(t+1) = 5(5t-1) +18
10t+10 = 25t-5+18
-15t = 3
t = -1/5
經驗算後，兩者答案是 4/15
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3) [4(2y-1)/20] + [5(1+y)/20] = 20/20 - [10(1-y)/20]
4(2y-1)+5(1+y) = 20-10(1-y)
8y-4+5+5y = 20-10+10y
3y = 9
y = 3
經驗算後，兩者答案是 2