Question

Se stie ca x+y=5.Determinati valoarea expresiei x la a doua +2xy+y la a doua-20 va rog ajutati-ma

Answer 1

$\rm x^2+2xy+y^2=(x+y)^2=5^2=\bold{25} \\ 25-20=\bold{5} \\ \\ \bold{Raspuns:5}$