數學幾題,急!!~~急!!~~急!!~~急!!~~數學幾題,急!!~~急!!~~急!!~~急!!~~

Q1. 1/2(4-3x)=1/3(3-4x)
12{1/2(4-3x)}=12{3/1(3-4x)}
6(4-3x)=4(3-4x)
24-18x=12-16x
-18x+16x=12-24
-2x=-12
x=6


Q2. 2/1(y+4)=y+1/8(4-y)
8{2/1(y+4)}=8{y+1/8(4-y)}
4(y+4)=8y+1(4-y)
4y+16=8y+4-y
4y-8y+y=4-16
-3y=-12
y=4


Q3. 4/5x-(-x+5)=-(x-3)-2/5(2+2x)
5{4/5x-(-x+5)}=5{-(x-3)-2/5(2+2x)}
4x-(-x+5)=-5x+15-2(2+2x)
4x+x-5=5x+15-4-4x
4x+x-5x+4x=15-4
4x=11
x=11/4

Q4. (x-1/3)+(x+1/4)=1/6
12[(x-1/3)+(x+1/4)}=12(1/6)
12x-4+12x+3=2
12x+12x=2+4-3
24x=3
x=3/24
x=1/8

Q5. 0.4-0.6(x-3)=1/3x-3/5(x-7)
15{0.4-0.6(x-3)}=15{1/3x-3/5(x-7)}
6-9(x-3)=5x-9(x-7)
6-9x+27=5x-9x+63
6+27-63=5x-9x+9x
-30=5x
-6=x
x=-6

Q6.不明白你想問甚麼