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(5分之7x)/(x-3)=4分之5x=?jixu

题目详情
(5分之7x)/(x-3)=4分之5 x=?
jixu
▼优质解答
答案和解析
解 :(7x/5) / (x-3) = 5x/4
交叉成得,28x = 25x(x-3)
即,28x = 25x^2 - 75x
25x^2 - 75x - 28x = 0
25x^2 - 103x = 0
x ( 25x -103 ) = 0
x = 0 或 x = 103/25