Respuesta :

let man's age be x
400-3x=163
-3x=-400+163
-3x=-237
/-3
x=79
age is 79 years

Answer:

79 years old

Step-by-step explanation:

Let his age be x

400-3x=163

400-163=3x

237=3x

Divide both side by 3

237/3 =3x/3

79=x

The man's age (x) =79 years old