Question

resolvas as equações do 2° grau
a) 4x²-36=0

Answer 1

$4 x^{2} -36=0\to\\\\ 4 x^{2} =36\to \\\\ x^{2} = \frac{36}{4} \to \\\\ x^{2} =9\to\\\\ x=\pm \sqrt{9} \to \\\\ x=\pm3\\\\\\ S= \left \{ -3;3\left \}$

Answer 2

a)  4x² - 36 = 0 
Δ = 0² - 4 . 4 . (- 36)               X = - 0 +- √576  / 2 . 4
Δ = 576                                 X = +- 24  / 8
x' = 24  / 8 = 3              x" = - 24  / 8 = - 3