Explanation:
Let age of rick = x
age of sara = y
age of marcos = a
age of jade = b
Rick is 4 years younger than Sara.
x = y - 4
Marcos is 3 years older than Jade.
a = b + 3
Rick's age is twice the age of Marcos and Jade's ages combined.
x = 2(a+b)
The youngest is 9 years old.
The youngest is jade because rick and sara are the parents and marcos is older than she is.
b = 9
How old is each??
a = b + 3
a = 9 + 3 = 12
Marcos is 12 years old
x = 2(a+b)
x = 2 (12 + 9)
x = 2 (21) = 42
Rick is 42 years old
x = y - 4
42 = y - 4
y = 42 + 4 = 46
Sara is 46 years old