Answer:
15.
Explanation:
Let his age now be x years. Then:
(x - 3)^2 = 6(x + 9)
x^2 - 6x + 9 = 6x + 54
x^2 - 12x - 45 = 0
(x - 15)(x + 3) = 0
x = 15, -3
We ignore the negative so his age now is 15.
Age= 15
Let a be for age at the moment
(a-3)^2 =6(a+9)
a^2-6a+9=6a+54
a^2-12a-45
(a-15)(a+3)
a=15 or a=-3
Age cannot be negative (-)
Therefore
Age =15
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