👤
a fost răspuns

2x+2y=82
(x+4)(y-5)=xy

Răspuns :

MadalinaMadutaa
2x+2y=82
(x+4)(y-5)=xy

2*(x+y)=82
xy-5x+5y-20=xy

x+y=82/2
5*(-x+y)=xy+20-xy

x+y=41
-x+y=20/5

x+y=41
-x+y=4
---------- +
/ 2y=45
y=45/2
y=22,5

x+y=41
x=41-y
x=41-22,5
x=18,5