Question

81x²-9=0

I have to use the Qaudratic Formula

Answer 1

$81x^2-9=0 \\ \\ (9x-3)(9x+3)=0 \\ \\9x-3=0 \ \vee \ 9x+3=0\\ \\9x=3/:9 \ \vee \ 9x=-3/:9\\ \\ x= \frac{3}{9} \ \vee \ x=- \frac{3}{9}\\ \\ x= \frac{ 1}{ 3} \ \vee \ x=- \frac{ 1}{3}$