SOLUTION: Jack is 4 times as old as Lacy. 7 years ago the sum of their ages was 51. How old are they now?

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Question 1050030: Jack is 4 times as old as Lacy. 7 years ago the sum of their ages was
51. How old are they now?

Answer by addingup(3677)   (Show Source): You can put this solution on YOUR website!
For my convenience, I'll let Jack be J and Lacy be L. If they're asking you to use x and y you can change the letters.
:
J = 4L We'll use this value for J next
J-7+L-7 = 51 Substitute for J
4L-7+L-7 = 51
5L-14 = 51
5L = 65
L = 13 So Lacy is 13 and Jack is 4*13 = 52
>>>>>>>>>>>>>>>>>>>
Check
7 years ago:
Lacy: 13-7 = 6
Jack: 52-7 = 45
Add them up:
6+45 = 51 Correct

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