Question

Solve:
$\sqrt{5^2\times 14-16\times 7+(4{)}^{?}}=18$

Answer 1

$\sqrt{5^2\times 14-16\times 7+(4{)}^x}=18$

$\sqrt{350-112+(4{)}^x}=18$

$\sqrt{238+(4{)}^x}=18$

squaring on both sides

$238+(4{)}^x=(18{)}^2$

$(4{)}^x=324-238$

$4^x=86$

$x=3.2132$