Respuesta :

Answer:

It is a right triangle

Step-by-step explanation:

Use the Pythagorean theorem:

[tex]a^2+b^2=c^2\\\\3.9^2+8.0^2=8.9^2\\\\15.21+64=79.21\\\\79.21=79.21[/tex]

if they weren't equal, it wouldn't be a right triangle.