👤
Ursuteodora9
a fost răspuns

Să se găsească toate numerele de forma xy15, ştiind că xy+yx=99.repede vrg​

Răspuns :

Dianageorgiana794

Răspuns:

[tex]xy+yx=99\\\\10x+y+10y+x=99\\\\11x+11y=99\\\\11(x+y)=99\\\\x+y=99:11\\\\x+y=9\\\\x=1;y=2\\\\x=2;y=7\\\\x=3;y=6\\\\x=4;y=5\\\\x=5;y=4\\\\x=6;y=3\\\\x=7;y=2\\\\x=8;y=1\\\\1815;2715;3615;4515;5415;6315;7215;8115[/tex]

Alte intrebari