Question

25 x elevado a 2 menos 1 e igual a 0

Answer 1

25x²-1=0
25x²=1
x²=1/25
x=√1/25= 1/5

Answer 2

$25x^2-1=0 \\ \\ 25x^2=1 \\ \\ x^2= \dfrac{1}{25} \\ \\ \\ x = \pm \sqrt {\dfrac{1}{25} } \\ \\ \\ \boxed{x= \pm\,\,\frac{1}{5} }$