Question

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

Answer 1

 12 = 4 x 3
12 = 6 x 2 
 x - 3 = 4      y + 2 = 3 
x = 4 + 3      y = 3 -2
x = 7            y = 1
( 7 - 3) x ( 1+2 )= 4 x 3 = 12

x - 3 = 6      y + 2 = 2
x = 6 - 3      y = 2 - 2 
x = 3          y = 0 

Answer 2

(x-3)(y+2)=12
a)12= 2*6
b)12=3*4
c)12=1*12

a)x-3=2; x=5
y+2=6; y=4

x-3=6   x=9
y+2=2   y=0

b)x-3=3; x=6
y+2=4; y=2
x-3=4; x=7
y+2=3; y=1

c)x-3=1; x=4
y+2=12; y=10

x-3=12; x=15
y+2=1; y=-1  ∉ N deci nu este solutie