Respuesta :
Answer:
a = ± 9
Step-by-step explanation:
The denominator of the rational expression cannot be zero as this would make it undefined. Equating the denominator to zero and solving gives the values that a cannot be
324 - 4a² = 0 ( subtract 324 from both sides )
- 4a² = - 324 ( divide both sides by - 4 )
a² = 81 ( take the square root of both sides )
a = ± [tex]\sqrt{81}[/tex] = ± 9 ← excluded values
