Math
posted by Vic on .
Maria is three times as old as her brother.In 4 years,Maria will be twice as old as he will be then.How old is Maria's brother now?

Help need equation

Let x = maria's age and y = her brother's.
x = 3y
(x+4) = 2(y+4)
Substitute 3y for x in second equation and solve for y. Insert that value into the first equation and solve for x. Check by inserting both values into the second equation. 
6=24

y=4
x=12 
Lindana