Question

determina numerele naturale x, y, astfel incat: (x-3)•(y+2)=12

Answer 1

Factorii care dau inmultiti 12 sunt:
1 x 12
2 x 6
3 x 4
4 x 3
6 x 2
12 x 1
a) 1 x 12 = 12 ==> x - 3 = 1 ==> x = 4; y + 2 = 12 ==> y = 10.
b) 2 x 6 = 12 ==> x - 3 = 2 ==> x = 5; y + 2 = 6 ==> y = 4
c) 3 x 4 = 12 ==> x - 3 = 3 ==> x = 6; y + 2 = 4 ==> y = 2
d) 4 x 3 = 12 ==> x - 3 = 4 ==> x = 7; y + 2 = 3 ==> y = 1
e) 6 x 2 = 12 ==> x - 3 = 6 ==> x = 9; y + 2 = 2 ==> y = 0
f) 12 x 1 = 12 ==> y + 2 = 1 ==> y = -1 (F)
        R: (x,y)e{(4;10);(5;4);(6;2);(9;1)}