<PRE><B>Question 1053736</B>
If I multiply my age (a) when I was 20 years younger with my age when I am 6 years older I get 5760 how old am I? 
:
(a-20)*(a+6) = 5760
FOIL
a^2 + 6a - 20a - 120 = 5760
a^2 - 14a - 120 - 5760 = 0
a^2 - 14a - 5800 = 0
You can use the quadratic formula to solve this, but it will factor to
(a-84)(a+70) = 0
the positive solution
a = 84 is your present age
:
:
See if that checks out
64 * 90 = 5760</PRE>