中一數學問題,4題,要步驟嫁,10分!!!!!!!!!!!!!!!!!!!!!!!!

1.x[x-2(x+1)]-1=8x+25
x(x-2x-2)-1=8x+25
x(-x-2)-1=8x+25
-x^2-2x-1=8x+25
0=x^2+10x+26

(Factorize 唔到.請問有冇抄錯題)

2.3又1/2+1又2/3m=1又5/6-1又1/4m
7/2+ (3m+2)/3m=11/6-(4m+1)/4m
(3m+2)/3m+(4m+1)/4m=11/6-7/2
(12m+8+12m+3)/12m = (11-21)/2
(24m+11)/12m = -10/2 = -5
24m+11 = -60m
84m = -11
m= -11/84

3.4/5x-(5-x)=1/3(x-3)-2/5(2+2x)
唔清楚條題目, (x-3) 和 (2+2x) 是在分子還是分母

4.1/4[1/3(2n+1)-1]=1/2+(1-3n/4)
1/4[(2n+1-3)/3]=2/4+(4-3n)/4
(2n-2)/3=2+4-3n
2n-2=(6-3n)*3
2n-2=18-9n
11n= 20
n=20/11
這題都係唔明條題目
我當[1/3(2n+1)-1]在分子, 3n/4是一個數., 1是分開的

第一,二題我識,但係佢係root form (根式)


2. 3又1/2+1又2/3m=1又5/6-1又1/4m
7/2+5/3m=11/6-5/4m
42/12+20/12m=22/12-15/12m
42/12-22/12=-15/12m-20/12m
20/12=-35/12m
20=-35m
m=20/-35
m=-4/7





4.1/4[1/3(2n+1)-1]=1/2+(1-3n/4)
1/4[2n/3+1/3-1]=1/2+1-3n/4
2n/12+1/12-1/4=3/2-3n/4
12*(2n/12+1/12-1/4)=(3/2-3n/4)*12
2n+1-3=18-9n
2n+9n-2=18
11n=18+2
11n=20
n=20/11