Answers

  • Brainly User
2016-04-22T06:55:45+08:00
Present ages:
     Nicole: 18
     Annie: 14

Let x be the years ago when Nicole was twice as old as Annie.

Ages x years ago:
     Nicole: 18-x
     Annie:  14 - x

Equation:
     18 -x = 2 (14 - x)
     18-x = 28 - 2x
     2x - x = 28 - 18
     x = 10

ANSWER: 10 years ago.

Check:
Ages 10 years ago: (substitute 10 for x)
Nicole: 18 - x   ⇒     18-10 = 8 years old
Annie:  14 - x   ⇒     14-10 = 4 years old

10 years ago, Nicole was twice as old as Annie:
8 = 2(4)
8 = 8    (True)
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