Respuesta :

Answer:

11.4

Step-by-step explanation:

By Pythagoras Theorem:

[tex]x^{2} = {7}^{2} + ( {4}^{2} + {8^{2}}) \\ \\ x^{2} = 49+(16 + 64)\\ \\ x^{2} = 49+80\\ \\ x^{2} = 129 \\ \\ x = \sqrt{129} \\ \\ x = 11.3578167 \\ \\ x = 11.4[/tex]

What the person said 11.4