If x and y are positive and x^2 * y^2 = 18 – 3xy, then x^2 =?(xy)^2+3(xy)-18=0
--> solving for xy
(not a valid solution: xy
must be positive as both unknowns are positive) or xy=3
--> so xy=3
Hope it's clear.
Hi Bunuel - thanks for your swift response.
Where I can get similar question like these for practice?
I have done the roots and equation set in your signature, are there any other sets that I can use for practice? Sincere thanks!