You can put this solution on YOUR website!
Let the base be
, then the height is
Since the area is given by
, you can just substitute:
Distribute, collect like terms, and put the equation into standard form for a quadratic:
Solve this by factoring, recognizing that
One of your roots will be a negative value. Exclude that root because it is extraneous introduced by the act of squaring the variable. The other root will be the length of the base.