Question

afla terminul necunoscut
5xy+36=81 a:7+7=11 36:c-8=1
ajutati-ma va rog dau coroana

Answer 1

5xy=81-36
5xy=45
xy=9
xy apartine D9
D9 apartine (1,3,9,-1,-3,-9)

a:7+7=11
a:7=11-7
a:7=4
a=4x7
a=28

36:c-8=1
36:8=1+8
36:c=9
c=36:9=4

Answer 2

5xy+36=81=> 5xy=81-36=45
xy=9=> x,y∈D9
D9∈{1, 3, 9, -1, -3, -9}
1) x=1, y=9
2) x=3, y=3
3) x=9, y=1
4) x=-1, y=-9
5)x=-3, y=-3
6) x=-9, y=-1
(x,y)∈{(1,9); (3,3); (9,1); (-1,-9); (-3,-3); (-9, -1)}

a:7+7=11=>a:7=4
a=28

36:c-8=1 => 36:c=9
36=9c
c=4

R: (x,y)∈{(1,9); (3,3); (9,1); (-1,-9); (-3,-3); (-9, -1)}
     a=28
     c=4