1)5(х-у)^2= 5(х^2-2ху+у^2)= 5*6,25-5*22,5+5*20,25=20.
2)3(х-у)^2= 3(х^2+2ху+у^2)=3*6,25+3*22,5+3*20,25=147.
1)5(х-у)^2= 5(х^2-2ху+у^2)= 5*6,25-5*22,5+5*20,25=20.
2)3(х-у)^2= 3(х^2+2ху+у^2)=3*6,25+3*22,5+3*20,25=147.