Question

Determinati nemerele naturale x și y , stiind ca (x-1) × (y+4) = 20​

Answer 1

x=ℕ {2,3...9} diferit de 0

y=ℕ {0,1,2,3...9}

Caz 1 :

(2-1)×(0+4)=1×4=4 (Fals)

Caz 2:

(3-1)×(4+4)=2×8=16 (Fals)

Caz 3:

(3-1)×(5+4)=2×9=18 (Fals)

Caz 4:

(6-1)×(0+4)=5×4=20 (Adevarat)

x=6 , y=0

Answer 2

(x-1) x (y+4) = 20| -3
x • y= 17