Question

Exercițiu mate 2)
x²-9=0

Answer 1

x² - 9 = 0 
x² = 9 
x = +- √9 
x = +- 3 

Answer 2

$x^{2} -9=0=\ \textgreater \ x^{2} =9=\ \textgreater \ x_{1,2} =+/- \sqrt{9} =\ \textgreater \ x_{1,2} =+/-3$

$Deci$   $x_1=3$   $sau x_2=-3$