6 grade math
posted by Annia .
This Christmas,your brother Jack will be 2 years from being twice as old as your sister Jen.The sum of Jack's age and three times Jen's age is 66.How old is Jen?

Let x be Jack's age.
Let y be Jen's age.
x = 2y  2
x + 3y = 66
So:
2y  2 + 3y = 66
5y  2 = 66
5y = 68
y = 13.6.
So she's about 13 and a half years old.