Respuesta :

Answer:

What are the roots of the quadratic equation x²-81=0

Answer:

x = ± 9

Step-by-step explanation:

Given

x² - 81 = 0 ( add 81 to both sides )

x² = 81 ( take the square root of both sides )

x = ± [tex]\sqrt{81}[/tex] = ± 9

Thus roots are x = - 9, x = 9