Answer:
x = 10
Step-by-step explanation:
10^2= 20, therefore
x = ± 2[tex]\sqrt{5}[/tex]
Given
x² = 20 ( take the square root of both sides )
x = ± [tex]\sqrt{20}[/tex] = ± [tex]\sqrt{4(5)}[/tex] = ± [tex]\sqrt{4}[/tex] × [tex]\sqrt{5}[/tex] = ± 2[tex]\sqrt{5}[/tex]