(6x一30):(5x十20)=3:4

5x一x十14=20 4(x一3)=7(x一6)解方程 (一x十2x的平方十5)十(4x的平方一3一6x) (6X一30):(5x十20)=3:4 (6x一30):(5x十20)=3:4 5x一3/4x平方一9一6x十9/4x平方一9十3x+15/4x平方9=? 10(3x十2)一20=5(2X一1)一4(2x十1) 已知1十x十x^2 十x^3=0,求x十x^2十x^3十x^4+x^5十x^6+x^7十x^8的值 5x一3x十4一1十3=12 x二? 5x十2x=42 15十2x一3=48 2x十3x十17=37 6x一3x=6÷5 9x一2x=15x十2x=4215十2x一3=482x十3x十17=376x一3x=6÷59x一2x=1.4十0.077(2x一6)=15.4 3x十7x十5x一7x=17十18 3(2x一1)十5(1一2x)十2x十4=0怎么解 一(x2十3X)十2(4X十x2),其中X=一2 (1)3X十6X一5=0 (2)4X一X一9=0, 7(x十4)=2(2一x)十3(4x一2) 6(2x一7)=5(x十8)十9 5(1十2x)=3(x一2)十3(17一x) 4（x十5一7）十2（3一x）=5 1/x^2一6x十8=1/x^2一4x十3x^2一6x十8和x^2一4x十3 (2x三次方一x十6)x(3x2十5x一2) (x十3)(x十4)一x(x+2)一5