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?
Math - PsyDAG, Thursday, December 10, 2009 at 11:05am
Let x = Jack's age
Let y = Jen's age
From the information above:
2y = x - 2
x + 3y = 66
Get x on one side for the first equation.
x = 2y + 2
Substitute 2y + 2 for x in the second equation and solve for y. Put that value in the first equation to solve for x. Check by inserting both values into the second equation.
I hope this helps.