Answer:
Square root of 4 is 2
so 1+
=4
frac{[1+sqrt{2x-1]}^2 }{4}=3
so 1+sqrt{2x-1]}^2=12
so 1+sqrt{2x-1}=V12
sqrt{2x-1}=V12-1
2x-1=(V12-1)^2=12-2V12+1=13-2V12
2x=13+1-2V12
2x=14-2V12
x=7-V12
x=7-2V3
I put an attachment to explain better
Explanation: