Question

la solución de la ecuación x2-81=0 es

Answer 1

x^2-81=0
x^2=81
√(x^2)=√(81)=
x=9

Answer 2

$x^{2} -81 = 0$

$x^{2} = 81$

$\sqrt{ x^{2} } = \sqrt{ 9^{2} }$

X =  ± 9

CS = { -9; +9}