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soopo
Oct15-09, 03:35 PM
1. The problem statement, all variables and given/known data

Solve the following equation for `a`.
(ab)^2 + ab - a^2 - 4b^2 = 0


3. The attempt at a solution

ab( ab + 1 ) - a^2 -4b^2 =

I perhaps should now use some sort of Diophantine equation.
However, I am not sure.

Dick
Oct15-09, 03:44 PM
Just treat it as a quadratic equation in 'a', regarding 'b' as a constant.

sara_87
Oct15-09, 03:46 PM
hiya,

treat b like a constant.
maybe the best way to solve this for a is to put the equation in the form of a quadratic, like:
ax^2+bx+c=0
(in this case you will have a instead of x) then use the quadratic formula to find the value(s) for a.

HallsofIvy
Oct15-09, 03:56 PM
Just treat it as a quadratic equation in 'a', regarding 'b' as a constant.

hiya,

treat b like a constant.
maybe the best way to solve this for a is to put the equation in the form of a quadratic, like:
ax^2+bx+c=0
(in this case you will have a instead of x) then use the quadratic formula to find the value(s) for a.
Two great minds with a single thought!