La suma de las edades de A y B es de 84 años, y B tiene 8 años menos que A?

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<img src="https://tex.z-dn.net/?f=La~ecuaci%5Cacute%7Bo%7Dn~seria%3A%20%20%5C%5C%20%20%5C%5C%20B%3DA-8~~------%5C%20%5Ctextgreater%20%5C%20%28II%29%20%5C%5C%20%20%5C%5C%20%5Cmathbb%7Bppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp%7D%20%5C%5C%20Ahora~reemplazamos~%28II%29~en~%28I%29~vea%3A%20%5C%5C%20%20%5C%5C%20A%2BB%3D84~~--%5C%20%5Ctextgreater%20%5C%20siendo%5BB%3DA-8%5D%20%5C%5C%20%20%5C%5C%20A%2BA-8%3D84%20%5C%5C%20%20%5C%5C%202A%3D92%20%5C%5C%20%20%5C%5C%20%5Cboxed%7B%5Cboxed%7BA%3D46%7D%7D~~~---%5C%20%5Ctextgreater%20%5C%20a%5Ctilde%7Bn%7Dos%5C%5C%20%20%5C%5C%20%20" />

<img src="https://tex.z-dn.net/?f=Como~sabemos~el~valor~de~%28A%29~es~s%5Cacute%7Bo%7Dlo~reemplazarlos~en~una~de%20%20%5C%5C%20las~ecuaciones~para~calcular~el~valor~de%20%28B%29%2C%20en~mi~caso~reemplazar%5Cacute%7Be%7D%20%5C%5C%20en~la~%28II%29~vea%3A%20%20%5C%5C%20%20%5C%5C%20B%3DA-8~~~--%5C%20%5Ctextgreater%20%5C%20Tenemos~%5BA%3D46%5D%20%20%5C%5C%20%20%5C%5C%20B%3D46-8%20%5C%5C%20%20%5C%5C%20%5Cboxed%7B%5Cboxed%7BB%3D38%7D%7D~~--%5C%20%5Ctextgreater%20%5C%20a%5Ctilde%7Bn%7Dos%5C%5C%20%20%5C%5C%20%5C%5C%20%5Cmathbb%7Bqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq%7D%20%20%5C%5C%20~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~Espero~te~sirva%2C%20saludos%21%21" />.