我有d maths 唔識 大家可唔可以教吓我

4(x-0.1)^2 = (2x-0.3)^2

4(x^2 + (0.1)^2 - 2x(0.1)) = (2x)^2 + 0.3^2 - 2(2x)(0.3)

4x^2 + 0.04 - 0.8x = 4x^2 + 0.6 - 1.2x

0.04 - 0.8x = 0.6 - 1.2x

0.4x = 0.56

x = 1.4

2009-05-16 18:29:39 補充：
唔好意思...上面有錯~~
睇呢個↓↓
4(x-0.1)^2 = (2x-0.3)^2

4(x^2 + (0.1)^2 - 2x(0.1)) = (2x)^2 + 0.3^2 - 2(2x)(0.3)

2009-05-16 18:29:56 補充：
4x^2 + 0.04 - 0.8x = 4x^2 + 0.09 - 1.2x

0.04 - 0.8x = 0.09 - 1.2x

0.4x = 0.05

x=0.125

我用一個同001有d唔同既方法做一次。
4(x-0.1)2 = (2x-0.3)2
[2(x-0.1)]2=(2x-0.3)2
2(x-0.1)=2x-0.3 或 2(x-0.1)=-(2x-0.3)
2x-0.2=2x-0.3 或 2x-0.2=-2x+0.3
無解 或4x=0.5
x=0.125//

4[X^2-2(X)(0.1)+(0.1)^2]=(2X)^2-2(2X)(0.3)+(0.3)^2

4X^2-0.8X+0.01=4X^2-1.2X+0.09

-0.8X+1.2X=4X^2-4X^2+0.09-0.01

0.04X=0.08

X=0.08/0.04

X=2

4^2=4既2次方

2009-05-16 16:20:13 補充：
以下先係正確,唔好意思

4(X-0.1)^2=(2X-0.3)^2

4[X^2-2(X)(0.1)+(0.1)^2]=(2X)^2-2(2X)(0.3)+(0.3)^2

4(X^2-0.2X+0.01)=4X^2-1.2X+0.09

4X^2-0.8X+0.04=4X^2-1.2X+0.09

-0.8X+1.2X=4X^2-4X^2+0.09-0.04

0.4X=0.05

X=0.05/0.4

X=0.125

4^2=4既2次方