(2) solution: x? -x= 1 x？ -x+ 1/4 (quarterly) =5/4 (x+ 1/2)? = 5/4 x+ 1/2 = √ 5 (root number 5)/2 x 1= half plus root number five x2= half minus root number five.

(3) solution: x? +2x-4/3=0 x？ +2x+ 1=7/3 (x+ 1)？ = 7/3 x+ 1 =√7/√3 x 1 = 1+√7/√3 x2 = 1-√7/√3

(4) Solution: 3x (x+1) = 3 (x+1) (3x-3) = 0x+1= 0 or 3x-3 = 0x 1 =-66.

(5) Solution: (2x-2)? =(x+3)？ (2x-2+x+3) (2x-2-x-3) = 0 3x+1= 0 or x-5=0 x 1=- 1/3 x2=5.

2. solution: let the even number be X.

x(x+2)= 168

x？ +2x= 168

x？ +2x+ 1= 169

(x+ 1)？ = 169

x+ 1= 13

X 1=- 14 (excluding) x2= 12, so one is 12 and the other is 14.

3. solution: let an edge be x.

x(x- 14)=48

(x-6)(x-8)=0

x 1=6 x2=8

So one right angle side is 6cm and the other is 8cm.

Look at this equation horizontally.