Answer:
[tex]\{-\frac{5}{2}\ ,\ \frac{5}{2} \}[/tex]
Step-by-step explanation:
SOLVING THE EQUATION :
4x² - 9 = 16
⇔ 4x² = 16 + 9
⇔ 4x² = 25
⇔ 2² × x² = 25
⇔ (2x)² = 25
⇔ (2x)² = 5²
⇔ 2x = 5 or 2x = -5
⇔ x = 5/2 or x = -5/2
