Question

Equações do 2grau !!! Me ajuda gente !!!!
A: X sobre 2 +25=0

B: 3x sobre 2 + 15 =0

C: (x+2 sobre 2 +(x-2)sobre 2-106.

Answer 1

Vamos lá:

a)
$x^2+25=0 \\\\ x^2=-25 \\\\ x=\pm\sqrt{-25} \\\\ x = \phi$
b)
$3x^2+15=0 \\\\ 3x^2+15=0 \\\\ 3x^2=-15 \\\\ x^2=-\frac{15}{3} \\\\ x^2=-5 \\\\ x=\pm\sqrt{5} \\\\ x=\phi$
c)
$(x+2)^2+(x-2)^2-106=0 \\\\ x^2+4x+4+x^2-4x+4=106 \\\\ 2x^2+8=106 \\\\ 2x^2=106-8 \\\\ 2x^2=98 \\\\ x^2=\frac{98}{2} \\\\ x^2=49 \\\\ x=\pm\sqrt{49} \\\\ x=\pm7$

Espero ter ajudado.