Respuesta :

jessicasyasya

Answer:

9/2

Step-by-step explanation:

[tex]4 {x}^{2} = 81 \\ {x}^{2} = \frac{81}{4} \\ x = \frac{ \sqrt{81} }{ \sqrt{4} } \\ x = \frac{9}{2} [/tex]

uwishuwerenik

Answer:9/2 and -9/2

Step-by-step explanation:

i just did it