Question

x ao quadrado -90=31

Answer 1

x² - 90 = 31

x² = 31 + 90

x² = 121

x' = √121 = 11

x'' = -√121 = -11

Answer 2

x^2 - 90 = 31

$x = \sqrt{121}$

X = 11

$x = -\sqrt{121}$

x =-11