How do you find it? Solve

y = 2 + √ [ y^2 - 12 ]         subtract 2 from both sides

y - 2 =  √ [y^2 - 12 ]         square both sides

( y - 2)^2 = y^2 - 12

y^2 - 4y + 4  = y^2 - 12       subtract y^2 from both sides

-4y + 4 = -12        subtract 4 from both sides

-4y = -16       divide both sides by -4

y = 4

Check that this solution works in the original equation, GM....