how do i solve this equation?

21(X-(1/7))^2= 3/7

thx

Divide both sides by 21
Take the square root of both sides.

Rewrite it as
x - (1/7)= sqrt [(1/21)*(3/7)]
= sqrt[(1/7)*(1/3)(1/7)]
= (1/7) sqrt(1/3)
x = (1/7)[1 + sqrt(1/3)]

tahnks

x=(2)/(7),0