解方程:5/8x(x-0.3)=75%

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解方程:5/8x(x-0.3)=75%解方程:5/8x(x-0.3)=75%解方程:5/8x(x-0.3)=75%5/8x(x-0.3)=75%两边乘8/5x²-0.3x=6/5x²

解方程:5/8x(x-0.3)=75%
解方程:5/8x(x-0.3)=75%

解方程:5/8x(x-0.3)=75%
5/8x(x-0.3)=75%
两边乘8/5
x²-0.3x=6/5
x²-3x/10+9/400=6/5+9/400
(x-3/20)²=489/400
x-3/20=±√489/20
x=(3-√489)/20,x=(3+√489)/20

5/8x(x-0.3)=75%
5/8x^2-3/16x=3/4
10x^2-3x-12=0
x=(3±√489)/20

解5/8x-15/80=0.75
5/8x=15/16
x=1.5