Answer:
x = ± 2[tex]\sqrt{5}[/tex]
Step-by-step explanation:
Given
4x² - 5 = 75 ( add 5 to both sides )
4x² = 80 ( divide both sides by 4 )
x² = 20 ( take the square root of both sides )
x = ± [tex]\sqrt{20}[/tex]
= ± [tex]\sqrt{4(5)}[/tex]
= ± 2[tex]\sqrt{5}[/tex]