SOLUTION: Write a system of equations and solve: Molly is 5 years younger than Heidi. In 3 years, Heidi will be twice as old as Molly. How old are they now?

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Question 4549: Write a system of equations and solve:
Molly is 5 years younger than Heidi. In 3 years, Heidi will be twice as old as Molly. How old are they now?
Answer by guapa(62) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = Molly's age (smaller number) x+5 = Heidi's age. Then x+3 = Molly's age in 3 years. (x+5)+3 = Heidi's age in three years.
x+3= (x+5)+3 Now in 3 years Heidi will be twice as old as Molly. so,
2(x+3)=(x+5)+3
2x+6=x+5+3
2x-x=5+3-6
x=2
Thus, Molly is 2 years and Heidi 7. In three years Molly will be 5 and Heidi 10. 10 = twice Molly's age.