Question

Se stie ca x-y=9.determinati valoare expresiei 19+x la a doua -2xy+y la a doua
Ajutatima va rog.

Answer 1

$19+ x^{2} -2xy+ y^{2} = \\ =19+(x-y) ^{2} = \\ =19+9 ^{2} = \\ =19+81= \\ =\boxed{100}$