Answer:
first and fourth
Explanation:
x² - 4 = 0 ( add 4 to both sides )
x² = 4 ( take square root of both sides )
x = ±
= ± 2
that is x = - 2, x = 2
4x² = 16 ( divide both sides by 4 )
x² = 4 ( take square root of both sides )
x = ±
= ± 2
that is x = - 2, x = 2