Ответ на фото/////////////

Verified answer

x*y=40

x+y=13

x=13-y

(13-y)*y = 40

13y - y^2 - 40 =0

-y^2 + 13y - 40 = 0

D=169-160=9 = 3^3

y1=8   y2=5

x1=13-8=5     x2=13-5=8

8*5=40

8+5=13