Respuesta :
Answer:
28
Step-by-step explanation:
Mikhail's age:x
Gabrielle's age:2x
x+2x=84
3x=84
x=84÷3
x=28
Let x be Gabrielle’s age
Let y be Mikhail’s age
X=2y and x+y=84 so...
X=2y and x=84-y so by substitution of x,
2y=84-y
3y=84
Y=28
So Mikhail is 28
And Gabrielle is 56
Let y be Mikhail’s age
X=2y and x+y=84 so...
X=2y and x=84-y so by substitution of x,
2y=84-y
3y=84
Y=28
So Mikhail is 28
And Gabrielle is 56