<PRE><B>Question 439847</B>
let a = his present age
;
15 years from now Isaac will be 8 times as old as he was 6 years ago.
a + 15 = 8(a-6)
a + 15 + 8a - 48
15 + 48 = 8a - a
63 = 7a
a = {{{63/7}}}
a = 9 yrs is his present age
:
:
Check this 
9 + 15 = 8(9 - 6) 
24 = 8(3); confirms our solution of a = 9 yrs 


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