Chapter 10 - Radical Expressions and Equations - 10-4 Solving Radical Equations - Practice and Problem-Solving Exercises - Page 623: 11

$b=8$

$Given,$ $\sqrt (2b)+4=8$ $\sqrt (2b)+4-4=8-4$ $\sqrt (2b)=4$ Squaring,we get: $2b=16$ $b=16\div2=8$ We need to check by putting the obtained value in the original equation : $L.H.S=\sqrt (2X8)+4=\sqrt 16+4=4+4=8=R.H.S$ Hence, $b=8$ is a valid solution