Answer:
[tex]x=\pm5[/tex]
Step-by-step explanation:
First, add 75 to each side.
[tex]3x^2-75+75=0+75\\3x^2=75[/tex]
Next, divide each side by 3.
[tex]x^2=25[/tex]
Now, you can take the square root.
[tex]x = \pm\sqrt25}[/tex]
[tex]x=\pm 5[/tex]