Answer:
David is 30
Jacob is 9
Step-by-step explanation:
The sum of David and Jacobs age is 39
d + j = 39
d = 39 - j
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Two years ago David was four times Jacobs age
(d - 2) = 4(j - 2)
d - 2 = 4j - 8
d = 4j - 6
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Set the equations equal
4j - 6 = 39 - j
5j = 45
j = 9
d = 4(9) - 6
d = 30
