Question

Помогите решить!!!
4/5 х2-45=0

Answer 1

$\frac{4}{5}x^2-45=0 \\\\ \frac{4}{5}x^2=45\\\\x^2=45: \frac{4}{5}\\\\x^2= \frac{225}{4}\\\\x=б \frac{15}{2}\\\\x=б7,5$