Question

raiz quadrada 3+x =raiz quadrada 9-x

Answer 1

$\sqrt{3+x} = \sqrt{9-x}$

$( \sqrt{3+x})^2=( \sqrt{9-x} )^2$

$3+x=9-x$

$x+x=9-3$

$2x=6$

$x= \frac{6}{2}$

$x=3$

verificação

$\sqrt{3+3} = \sqrt{9-3}$

$\sqrt{6}= \sqrt{6}$

S={3}