Question

3) Qual o valor de “x”
na equação 5x2 – 125 = 0. 

Answer 1

$5 x^{2}-125=0$
$5 x^{2}=125$
$x^{2}= \frac{125}{5}$
$x^{2}=25$
$x= \sqrt{25}$
$x=5ou-5$

Answer 2

$5x^2-125=0\\\\ x^2-25=0\\\\\ x^2 = 25\\\\ \boxed{x=+\ ou-\ 5}$