Question

2x² - 8 = 0 Qual a resposta me ajudem pfvr <3


3z² - 70 = 5

Answer 1

Resposta:

$2x^2-8=0\\ \\ 2x^2=8\\ \\ x^2=8\div2\\ \\ x^2=4\\ \\ x=\pm\sqrt{4} \\ \\ x=\pm2\\ \\ S=\{-2,2\}\\ \\ -----------------\\ 3z^2-70=5\\ \\ 3z^2=5+70\\ \\ 3z^2=75\\ \\ z^2=75\div3\\ \\ z^2=25\\ \\ z=\pm\sqrt{25} \\ \\ z=\pm5\\ \\ S=\{-5,+5\}$